The last thing I remembered was the screech of tires and a woman's scream. Then darkness.
Death wasn't supposed to feel like a hangover. Yet here I was, head pounding, body aching, and distinctly not dead—at least not in any conventional sense.
My eyes fluttered open to an unfamiliar ceiling. Posters of anime girls in questionable poses stared down at me. Not my room. Not my posters. Not my taste.
"What the hell..." I muttered, pushing myself upright. The voice that came out wasn't mine either—higher, younger.
My hand instinctively reached for the nightstand where I usually kept my security baton—a habit from three years working high-risk security details. Nothing there. Just some... tissues and manga? Christ.
Something was very, very wrong.
I stumbled to the bathroom, my trained instincts screaming that I was in an unknown environment. The security officer in me was cataloging details, looking for threats, plotting escape routes. But when I reached the mirror, threat assessment became the least of my concerns.
Brown hair. Brown eyes. A teenage face I recognized all too well from countless anime episodes.
"Issei Hyoudou," I whispered, watching the stranger's lips form my words.
I wasn't Andrew Slayn anymore—the twenty-one-year-old security officer with a black belt in Karate and weapons training. Not the guy who worked double shifts handling drunks at high-end nightclubs and occasionally doing personal protection for visiting businesspeople. Not the anime enthusiast who spent hours mastering the Dark Knight rotation in Final Fantasy XIV.
I was somehow inside the body of a fictional character from High School DxD—a world filled with devils, fallen angels, and creatures that could kill me with a thought. A world I knew all too well from binge-watching sessions between shifts.
"This has to be a dream," I said, splashing cold water on my face. The sensation was too real.
"Not a dream, partner. Though I admit, this is... unusual."
The deep voice reverberated through my mind, causing me to stumble backward against the wall. I recognized the voice immediately—how could I not? I'd watched every episode multiple times.
"Ddraig?" I whispered. "The Welsh Dragon? Red Dragon Emperor?"
"You know of me." The voice sounded surprised, even impressed. "Most hosts require significant... persuasion before they even acknowledge my existence."
"Yeah, well, where I come from, you're fictional," I said, then laughed at the absurdity. "Though I guess that doesn't matter now."
"Fictional? How curious." The dragon's voice had a rumbling quality, like distant thunder contained in my skull. "Your mind contains strange knowledge. I see memories of... watching this world? As entertainment?"
"It's complicated." I ran a hand through unfamiliar hair. "But what's important is I know what's coming. Raynare. The Occult Research Club. Riser Phenex. Kokabiel. The list of things trying to kill Issei—I mean, me—is practically endless."
"Speaking of which," Ddraig interrupted, his tone shifting to something more serious, "we have a more immediate problem."
"We shouldn't be talking yet, should we?" I asked, my knowledge of the series timeline kicking in. "In the... story I know, you only start communicating with Issei after he's reincarnated as a devil and faces death again."
"Perceptive. No, this conversation should be impossible at this stage." Ddraig sounded almost amused. "But your soul is not what I expected. It's as if two souls occupy this vessel simultaneously—yours and the original owner's. Fused but distinct."
I looked down at my arms, expecting to see the red gauntlet of the Boosted Gear. Nothing. Instead, something heavy hung around my neck—a crimson amulet with emerald eyes that pulsed with inner light.
"The Boosted Gear looks different," I said, touching it carefully. My security training made me cautious—unknown objects were always potential threats.
"The sacred gear has adapted to your unique situation," Ddraig explained, and I could almost picture a massive dragon shrugging. "Your combined soul carries too much power, too much awareness for the standard form. Consider it... a mutation."
"That's not in the original story," I muttered. "What does that mean for—"
A sharp pain lanced through my chest, driving me to my knees. It felt like my heart was trying to burst from my ribcage. Years of training to handle physical attacks hadn't prepared me for pain from within.
"That," Ddraig said dryly, "is the sound of your body failing."
"What?" I gasped through the pain.
"Your human form cannot sustain the fusion of souls within it. The strain is too great." For a mythical beast of destruction, Ddraig sounded remarkably matter-of-fact about my impending death. "Without intervention, you will die within weeks. Perhaps days."
The pain subsided momentarily, leaving me panting on the cold bathroom floor. My mind raced through scenarios, threat assessments, contingencies—the security officer in me desperately searching for an exit strategy.
"Intervention? What kind of intervention?"
"There may be a way." Ddraig's voice took on an almost contemplative tone. "In my long existence, I've had hosts face similar issues—though none quite like yours. The solution is... extreme."
"I'm listening."
"To survive with such power, you must become something more than human. Parts of you must become dragon."
I laughed bitterly. "Like a partial transformation? Scales? Wings? What are we talking about here?"
"Internal, primarily. Heart. Lungs. Blood. The core systems that sustain life, replaced with draconic equivalents."
"And the success rate of this... procedure?" The security professional in me needed the risk assessment.
A pause. "Low. Perhaps thirty percent for the first transformation alone. Each subsequent change carries similar risk."
I absorbed this silently. In my job, I'd learned to calculate odds quickly. Thirty percent was terrible—but zero percent, which was my alternative, was worse.
"And if I refuse?"
"You die. The body fails. Both souls lost." Ddraig sounded almost sympathetic now. "I lose another host before they even accessed my power. Quite disappointing, really."
"Glad to know my death would inconvenience you," I muttered sarcastically.
"After millennia of imprisonment, one develops a certain... perspective," Ddraig replied, equally sarcastic. I hadn't expected the apocalyptic dragon to have a sense of humor.
I thought about everything I knew was coming in this world. Fallen angels with light spears. Devils with destruction magic. Gods and monsters from every mythology. As a security officer, I'd handled drunks and the occasional armed assailant—nothing that prepared me for cosmic powers waging wars with humanity caught in the middle.
But I did have one advantage—knowledge. I knew the players, the threats, the timeline. And I had training most teenagers didn't—hand-to-hand combat, weapons handling, threat assessment, tactical thinking.
"How long do I have to decide?"
Another wave of pain hit me, this one worse than before. Blood trickled from my nose, bright red against pale fingers.
"Not long, partner. Your body is already beginning to fail." Ddraig's voice held no mockery now, just brutal honesty. "Hours, perhaps a day before damage becomes irreversible."
As the pain receded again, I made my decision. I wasn't going to die—not again. If surviving meant becoming something other than human, so be it. I'd adapt, like I'd adapted to every other challenge in my life.
"Do it," I said firmly. "Whatever it takes."
"Brave words." Ddraig sounded approving. "Or foolish. Often the same thing."
"Save the philosophy lesson. How do we start?"
The emerald eyes of the amulet flared to life, casting an eerie green glow across the bathroom.
"First transformation will be the heart—most crucial, most dangerous. You'll need isolation. Privacy. The process is... not quiet."
"Meaning?"
"Meaning you'll scream until your vocal cords rupture, only for me to heal them so you can scream more." Ddraig's brutal honesty was almost refreshing. "Three days of agony as your human heart dies and a dragon heart forms. Survival... uncertain."
I swallowed hard. In my security work, I'd broken bones, been stabbed once, and taken more punches than I could count. None of that would compare to what was coming.
"And after that?"
"If you survive, recovery. Adaptation. Learning to control a heart that pumps power as well as blood." The dragon almost sounded impressed by my lack of hesitation. "Then we plan the next transformation."
I nodded, military-style, short and decisive. "I have about six weeks of summer break before school starts. Six weeks until the original timeline events begin."
"Canon events?"
"Trust me, it's complicated." I pushed myself up from the floor, steadying against the sink. "But if we're changing things already, maybe I can change more. Play this smarter than the original Issei would have."
"The original owner of this body was... not strategically minded," Ddraig admitted with what sounded like draconic embarrassment. "His thoughts were dominated by breasts and harem fantasies."
"Yeah, well, my thoughts are dominated by staying alive," I replied grimly. "And using what I know to maybe save some lives along the way."
"A worthy goal." Ddraig sounded genuinely impressed now. "Very well, Andrew Slayn. Let us begin your transformation. It starts with pain, and will likely end with pain, but between..."
"Between, we fight," I finished. "And unlike Issei, I already know how."
My hand reached up to grip the amulet firmly. The security officer. The Dark Knight enthusiast. The man who died saving a stranger. All parts of who I was—who I would continue to be, even in this new form.
"Let's do this."
"It begins."
And with those words, my transformation into something beyond human—into a draconic warrior unlike anything this world had seen before—began its painful, uncertain course.
Welcome to my new life in High School DxD.
Gods, I hate my luck.
I left a note on the kitchen table that morning—vague words about staying with a friend for a few days of summer break, just enough to avoid suspicion from Issei's parents. Not that they seemed particularly attentive. In my first two days in this body, they'd barely glanced up from their newspapers and TV shows during our brief interactions.
"Issei's going out!" I called, forcing myself to use the third person as I made for the door.
His mother barely looked up from her morning coffee. "Don't forget, we're leaving for our business trip tomorrow. There's money on the counter for groceries."
His father grunted noncommittally from behind his newspaper. "Try to stay out of trouble for once."
The casual disinterest stung, even though these weren't my parents. Years of Issei's perverted antics had apparently conditioned them to expect the worst and hope for nothing better than absence of complaints from school.
"I'll be fine," I assured them, wondering if they'd even notice if I never returned. The thought brought a bitter taste to my mouth.
The abandoned storage unit on the outskirts of Kuoh had been surprisingly easy to find—an internet search, a phone call, and a small cash deposit from Issei's meager savings secured me three days of uninterrupted privacy. It wasn't much—concrete walls, a metal door with a sturdy lock, and enough space to set up the minimal supplies I'd need.
I arranged the items methodically: water bottles, protein bars, a sleeping bag, first aid supplies, and towels—lots of towels. The security professional in me had always prepared for contingencies, a habit that would serve me well in what was coming.
"This place should work," I said, sitting cross-legged in the center of the unit. "No one around to hear... whatever happens next."
"Adequate," Ddraig agreed. "Though you should secure yourself. The pain may cause violent convulsions."
I nodded grimly, using rope to create restraints I could tighten around my limbs. Security training had included preparing for worst-case scenarios, though never anything like this.
"How do we start?" My voice betrayed no fear, though my heart—still human for the next few hours—was pounding in my chest.
"Focus on the amulet. It contains the connection point between your soul and mine. Through it, draconic energy will replace your heart's human essence—gradually at first, then all at once."
I touched the crimson amulet, feeling its warmth against my palm. "And the pain?"
"Unavoidable. Necessary. Transformative." The dragon's voice was solemn. "Are you certain, Andrew Slayn? Once begun, this process cannot be reversed."
I thought of my options—death within days from soul rejection, or potential survival as something no longer fully human. The choice wasn't really a choice at all.
"Do it," I said, closing my eyes and gripping the amulet tightly. "I'm ready."
The first wave of pain hit like nothing I'd ever experienced—a thousand white-hot needles piercing my chest simultaneously. I gritted my teeth, security training kicking in as I tried to compartmentalize the agony. That lasted approximately three seconds.
Then I was screaming.
Three days.
They would forever stand as the most agonizing experience of both my lives. Three days that felt like three centuries, where time stretched and warped through a haze of pain so intense it defied description.
I remember fragments. Flashes. The feel of my own fingernails breaking against the concrete floor of the abandoned storage unit. The taste of blood as I bit through my tongue—repeatedly. The hoarse whispers that were all that remained of my voice after the first twelve hours of screaming.
And heat. Unbearable, searing heat that started in my chest and radiated outward as my human heart literally burned away, cell by cell, only to be replaced by something... other.
"You survived," Ddraig's voice was the first thing I clearly registered as consciousness returned fully. "Impressive. Most would have broken."
I lay motionless on the cold concrete, my body slick with sweat and blood, every muscle trembling with exhaustion. The simple act of breathing felt strange—deeper, more efficient, like each lungful of air contained twice the oxygen.
"Did it work?" My voice was a ragged whisper, yet surprisingly strong considering what it had been through.
"See for yourself."
With effort, I raised my hand to my chest. No heartbeat—at least, not a human one. Instead, a steady, powerful thrum pulsed beneath my palm, slower than a human heart but infinitely stronger. Every beat sent a wave of warmth through my body, a current of energy that felt both foreign and utterly natural.
"What... what am I now?" I asked, managing to push myself into a sitting position. The storage unit looked like a war zone—blood spatters on the walls, deep gouges in the concrete where my fingers had clawed during the worst moments.
"Still mostly human," Ddraig replied, with what almost sounded like pride. "But your core is dragon now. The heart of a fire drake pumps power through your veins alongside blood."
I looked down at my chest. The skin appeared normal, unmarked—but beneath it, I could feel something fundamentally different. Something powerful.
"The survival rate," I remembered through the fog of pain. "You said thirty percent."
"I was being generous," the dragon admitted. "I've only seen three hosts survive this particular transformation before you. None were mere humans—one was a half-god, another a descendant of heroes."
"And the third?"
A pause. "A stubborn fool who simply refused to die."
I laughed, then winced as the motion pulled at sore muscles. "Sounds familiar."
With careful movements, I used the wall to brace myself as I stood. My legs felt shaky but held. My security training kicked in automatically—assess, adapt, overcome.
"How long until I'm... operational?" I asked, defaulting to terminology from my previous life.
"Your recovery rate is remarkable," Ddraig observed. "The draconic heart accelerates healing. A day, perhaps two, before you regain full mobility. A week before you can access the first tier of power."
I nodded, mentally calculating. We were in the first week of summer break—almost seven weeks left before school resumed and Kuoh Academy would again be filled with students and, more concerningly, devils. Seven weeks to recover, learn to control my new abilities, and master energy suppression before I'd be walking the same hallways as Rias Gremory and her peerage. The timeline was tight, but I'd worked under pressure before.
"And the power? What can I do now that I couldn't before?"
"Your physical strength has doubled, perhaps tripled," Ddraig explained. "Your endurance, far more. Fire magic will come naturally to you now—an affinity born of your new heart. And you'll find yourself... changed in other ways."
"Changed how?"
"More aggressive. More instinctual. More... draconic." The ancient being sounded almost amused. "Dragons are creatures of power and instinct. You'll feel it most strongly in battle or... other intense situations."
Great. As if hormones weren't enough, now I had dragon instincts to contend with. But I'd manage—I always had.
I glanced down at my body—still the same lean teenage frame as before. "Shouldn't my muscles have changed too? If I'm stronger now?"
"Physical transformation is more complex than you might think," Ddraig explained. "Your strength comes from the draconic energy flowing through your system, not merely muscle mass. Though as you use this power, your body will gradually adapt to channel it more efficiently. You'll notice changes in time."
"The next transformation?"
"Not for at least a month maybe two," Ddraig warned. "Your body needs time to fully adapt. Rushing would kill you—and this time, I doubt even your stubbornness would save you."
I nodded, accepting the limitation. One, maybe two months to master what I'd gained before risking more.
Carefully, I made my way to the small backpack I'd prepared. Clean clothes, water, protein bars—the essentials I'd thought to bring before subjecting myself to this ordeal. Security work had taught me to always have contingencies.
As I changed out of my blood-soaked clothes, I noticed something odd in the cracked mirror propped against the wall. My eyes—Issei's eyes—had changed. The irises now held flecks of emerald green, glinting like tiny shards of jade against the brown.
"The first visible sign," Ddraig commented, noticing my focus. "There will be others as we progress."
I nodded, studying my reflection. The face was still Issei's—young, Japanese, unremarkable. But the eyes held something new. Something dangerous.
"We have work to do," I said finally, slinging the backpack over my shoulder. My body protested, but I ignored it. Pain was temporary. Death was permanent—and I'd already experienced that once.
"Indeed we do, partner," Ddraig agreed, his voice resonating through my new draconic heart. "The world won't be prepared for what we become."
I stepped out of the storage unit into the pale light of dawn, feeling the power thrumming beneath my skin with each beat of my transformed heart. Then a concerning thought struck me.
"Wait. The devils at Kuoh Academy—Rias and her peerage," I said, pausing in the doorway. "Won't they sense this change? In the series, they could detect powerful energies and sacred gears."
"A valid concern," Ddraig acknowledged. "Yes, those sensitive to magical energies might detect something different about you. The Gremory girl and her Queen would certainly notice if you flared your power carelessly."
"So I need to learn to suppress it," I concluded, adding another item to my growing to-do list. "Can you teach me that?"
"It's possible, yes. Another skill to master." There was a hint of wariness in Ddraig's tone. "But it will be challenging. Most hosts take months to develop such control."
"I don't have months. I have seven weeks before school starts again," I reminded him, feeling the pressure mounting. Two weeks to master an ability that should take months, all while recovering from a transformation that nearly killed me. "I'll have to learn faster."
"Your determination is admirable, if perhaps foolish," Ddraig rumbled, but I detected a note of respect beneath the criticism. "We'll begin tomorrow."
I nodded, mentally calculating how to approach Kuoh Academy without immediately drawing supernatural attention. Every advantage I could maintain, every element of surprise I could preserve, would be crucial in the coming weeks.
I had just reached the main road leading back toward town when another wave of pain hit—not as severe as during the transformation, but enough to make me stagger. My vision blurred as I leaned against a tree for support, breathing hard as the draconic heart adjusted something within my chest.
"Ddraig... what's happening?" I gasped through gritted teeth.
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"Secondary adaptations," he replied, concern evident in his voice. "Your body is still reconfiguring to accommodate the draconic heart. It will happen sporadically for the next few weeks."
Great. Random pain attacks in public. Exactly what I needed.
As the pain subsided, I became aware of someone watching me. Turning slightly, I caught a glimpse of pink hair disappearing behind a fence—a girl from Kuoh Academy, if I wasn't mistaken. Katase, one of the kendo club members who regularly chased the Perverted Trio for their peeping activities.
Had she seen my moment of weakness? How much had she observed? I couldn't afford witnesses to my strange condition this early in the timeline.
But I had more immediate concerns. I needed to return to Issei's home, prepare a training regime, and begin learning energy suppression techniques before anyone else noticed the supernatural changes happening within me.
"Neither will I," I murmured, referring to my earlier comment about being prepared for what I'd become. "But I'll adapt."
I always did.
Two weeks after the heart transformation, I was making progress. My physical recovery had been surprisingly quick—within days I was running laps around the neighborhood, pushing this teenage body harder than the original Issei ever had. Each morning I practiced the karate forms I remembered from my previous life, muscle memory gradually adapting to my new physicality.
The aikido techniques were trickier—they required a sensitivity to momentum and energy that my enhanced strength sometimes disrupted. But I practiced diligently, knowing these skills might eventually save my life against supernatural opponents.
Energy suppression remained the greatest challenge. Controlling the power emanating from my draconic heart required intense concentration, especially during physical exertion or emotional disturbance.
One evening, I was in the living room when a news report caught my attention—a traffic accident eerily similar to how I'd died as Andrew. A young woman had pushed a child out of the path of an oncoming car, sacrificing herself in the process.
The images hit me like a physical blow. Suddenly I was back there on that street corner, hearing tires screech, seeing the woman's face, feeling the impact—
The draconic heart contracted violently in my chest, responding to the emotional surge. Pain erupted like molten metal in my veins as power flared uncontrollably.
I doubled over, gasping, my hand clutching my chest as I fought to suppress the energy threatening to burst forth visibly. Sweat beaded on my forehead as I struggled for control, implementing the breathing techniques Ddraig had taught me.
"Issei?" My mother's voice cut through the haze of pain. She'd entered the room silently, carrying a basket of laundry, only to find her son apparently having some kind of cardiac episode. "Issei!"
The basket crashed to the floor as she rushed to my side. "What's happening? Are you alright?"
I couldn't answer immediately, all my focus directed inward as I battled the rebellious energy surging through my system. Each breath came labored and deliberate, the techniques only partially effective against the emotionally triggered flare-up.
"I'm... fine," I managed through gritted teeth, though my pale face and trembling hands clearly contradicted this claim.
"You are not fine!" she exclaimed, genuine fear replacing her usual passive demeanor. Her hands hovered uncertainly over me, afraid to touch yet desperate to help. "This looks like a heart attack! I'm calling an ambulance."
"No!" I grabbed her wrist as she reached for the phone, perhaps too quickly, too strongly. The look of surprise on her face made me immediately release my grip. "No ambulance. It'll... pass. Just give me... a minute."
Her eyes widened with concern as she took in my appearance - the unnatural pallor, the cold sweat, the trembling hands. "Issei... how long has this been happening?"
Gradually, painfully, I regained control, forcing the draconic energy back into containable channels. The pain subsided to a dull throb as my breathing steadied.
"I'm okay now," I assured her, straightening slowly. "Really."
She stared at me with a mixture of confusion and maternal terror I'd never seen before—not directed at me, anyway. "That was not okay, Issei. That looked like a serious cardiac event. How long has this been happening?"
I wiped cold sweat from my forehead, calculating quickly. The medical explanation would serve better than alternatives, and her witnessing an episode firsthand made denial impossible.
"A few weeks," I admitted, deciding honesty about the timeline was safe. "Started around the time I disappeared for those three days."
"And you didn't think to tell us?" Anger now mixed with her fear—the protective instinct of a mother discovering her child had been hiding a potentially life-threatening condition.
"I didn't want to worry you," I said, which wasn't entirely untrue. "It's probably nothing serious."
"Nothing serious?" she repeated incredulously. "Issei, your father and I thought you were just going through some teenage phase with all the exercise and studying. But this—" she gestured at me, still pale and trembling, "this is a medical emergency."
I shook my head. "It's not as bad as it looks. The episodes pass quickly."
"Episodes? Plural? How many times has this happened?"
I hesitated, then admitted, "A dozen or so. Usually when I'm stressed or... reminded of something upsetting."
She was already reaching for her phone again. "I'm calling Dr. Takeda right now. You need medical attention."
"Mom, really, I'm—"
"This isn't negotiable," she interrupted, her usually passive demeanor replaced by unexpected steel. "Either you see the doctor willingly, or I'll drag you to the emergency room myself."
I stared at her, genuinely surprised by the forceful response. Perhaps there was more to Issei's mother than the anime had portrayed—a core of protective instinct beneath the permissive parenting.
"A medical cover story might serve our purposes," Ddraig commented internally. "Explaining both the episodes and your need for those breathing techniques."
He was right, of course. A diagnosed condition would provide plausible explanation for behaviors that might otherwise raise suspicion.
"Fine," I conceded, calculating quickly. "But no emergency room. A regular doctor's appointment should be enough."
She nodded, some tension leaving her shoulders though concern still dominated her expression. "I'll call first thing in the morning. No arguments."
As she dialed Dr. Takeda's office, I heard her mutter, "First he disappears for three days, then comes back exercising at dawn, and now heart attacks on the living room floor. What happened to my perverted, lazy son?"
I couldn't help the small smile that formed. If she only knew the half of it.
That afternoon found me in Dr. Takeda's office, enduring a physical examination that I hoped wouldn't reveal anything beyond normal human parameters. The draconic heart was my greatest concern—its rhythm and strength were distinctly non-human.
Damn. One of the adaptation episodes had happened in the middle of the night. I'd thought everyone was sleeping.
"It's nothing," I tried to assure her. "Just... growing pains."
"Growing pains don't make people collapse," she said firmly. "I'm making an appointment with Dr. Takeda. Today."
"Mom, really, I'm—"
"This isn't negotiable," she interrupted, her usually passive demeanor replaced by unexpected steel. "Either you see the doctor willingly, or I'll drag you there myself."
I stared at her, genuinely surprised by the forceful response. Perhaps there was more to Issei's mother than the anime had portrayed—a core of protective instinct beneath the permissive parenting.
"Fine," I conceded, calculating quickly. A medical examination might actually provide useful cover for any future incidents. "But I'm telling you, it's nothing serious."
She nodded, some tension leaving her shoulders. "We'll let the doctor be the judge of that."
As she turned to go back inside, I heard her mutter, "First he disappears for three days, then comes back exercising at dawn and having chest pains. What happened to my perverted, lazy son?"
I couldn't help the small smile that formed. If she only knew the half of it.
That afternoon found me in Dr. Takeda's office, enduring a physical examination that I hoped wouldn't reveal anything beyond normal human parameters. The draconic heart was my greatest concern—its rhythm and strength were distinctly non-human.
"Well, your reflexes are excellent," the middle-aged doctor noted, setting aside his reflex hammer. "Better than I would expect for someone your age, especially given your previous check-ups."
I shrugged noncommittally. "I've been exercising more."
"So your mother mentioned." He picked up his stethoscope. "Now, let's listen to that heart of yours. She's quite concerned about chest pains you've been having."
This was the moment of truth. If he noticed anything significantly abnormal, it could lead to complications I wasn't prepared to handle. I focused intensely on suppressing the draconic energy, hoping it would mask some of the heart's unusual characteristics.
The cold metal touched my chest, and Dr. Takeda's brow furrowed immediately.
"Hmm," he murmured, moving the stethoscope across different positions. "Your heartbeat is... unusual."
"Unusual how?" I asked, trying to sound innocently curious rather than alarmed.
"Much slower than I would expect for someone your age, especially after mentioning chest pains." He moved the stethoscope again. "And the rhythm is somewhat... distinctive."
I feigned confusion. "Is that bad?"
"Not necessarily. Some athletes develop very slow heart rates due to intense conditioning." He removed the stethoscope, looking at me with professional assessment. "Though I wasn't aware you were an athlete, Issei."
"I've just started recently," I said quickly. "Running, mainly. And some martial arts."
He made notes on his clipboard. "Well, I'd like to run an ECG to get a better picture. The heart is not something we take chances with, especially in young people."
The examination continued with blood pressure readings (higher than normal), reflexes (significantly enhanced), and finally an ECG. Throughout the process, I maintained intense focus on energy suppression, though I worried it wouldn't be enough to mask the fundamental differences in my cardiovascular system.
Dr. Takeda returned with the ECG printout, a perplexed expression on his face.
"This is... quite unusual," he admitted, showing me the paper with its jagged lines. "Your heart has a pattern I've never encountered before. The electrical activity is significantly different from standard parameters."
I tried to look appropriately concerned while inwardly calculating how to spin this development to my advantage. "What does that mean? Is it dangerous?"
"I honestly can't say without further testing," he admitted. "The good news is that whatever this pattern is, it seems stable and strong—not the typical indicators of imminent heart failure. But these chest pains you've described are concerning."
He sat on his stool, considering me thoughtfully. "Can you describe these episodes in detail? When do they happen? What triggers them?"
I decided that partial truth would serve best here. "They usually happen when I'm stressed or exercising intensely. Sometimes just randomly. It feels like pressure building in my chest, then intense heat and pain that radiates outward. It only lasts a few minutes, then subsides."
"Any dizziness? Shortness of breath? Loss of consciousness?"
"Sometimes all of those," I acknowledged. "Though I haven't actually passed out yet."
He made more notes, then looked up seriously. "Issei, I think you need to see a cardiologist. These symptoms, combined with your unusual ECG, suggest something that requires specialized assessment. I'll make a referral, but in the meantime, I want you to avoid intense physical activity and practice those breathing exercises you mentioned if an episode begins. They might help manage the symptoms."
Perfect. A medical condition created the perfect cover for energy suppression techniques and any public episodes that might occur during adaptation phases.
"Is it... serious?" I asked, manufacturing appropriate teenage concern.
"I can't say definitively without more information," he replied honestly. "But given your age and otherwise excellent physical condition, I'm hopeful it's a manageable condition rather than something life-threatening."
When we returned to the waiting room, my mother rose anxiously. Dr. Takeda spoke to her quietly while I pretended not to listen, explaining the "unusual cardiac condition" that required further assessment but wasn't cause for immediate alarm.
Her relief was palpable, though concern lingered in her eyes. "So he'll be alright?"
"With proper monitoring and management, yes," the doctor assured her. "The referral to Dr. Miyazaki should come through within a week. Until then, moderation in physical activities and those breathing exercises he's been doing are actually beneficial for his condition."
The ride home was quiet, my mother occasionally glancing my way with a mixture of worry and something else—perhaps guilt for not noticing sooner that something was physically wrong with her son.
"I told you it wasn't serious," I said, attempting to ease her concern.
"A heart condition isn't 'nothing,' Issei," she replied quietly. "Why didn't you tell us you were having these pains?"
I shrugged, looking out the window. "I didn't want to worry you. And they're manageable."
"We're your parents," she said simply. "Worrying about you is our job."
Something in her tone made me look at her more closely. Despite the distance I'd sensed in their parenting style, there was genuine care beneath the surface—perhaps muted by years of dealing with the original Issei's troublesome behavior, but still present.
"I'll be more forthcoming in the future," I promised.
She nodded, seemingly satisfied with this commitment. "And you'll take it easy with the exercise? At least until we see the specialist?"
"I'll be careful," I agreed, already planning modifications to my training regimen that would be less visible while still developing the skills I needed.
As we pulled into the driveway, my mother turned to me with unexpected directness. "Whatever's happening with you, Issei—the exercise, the studying, the changed behavior—I want you to know that your father and I... we're glad to see you taking life more seriously. Even if it took chest pains to make it happen."
The simple statement caught me off guard. I hadn't expected approval from parents who seemed so disengaged from their son's life.
"Thanks, Mom," I said quietly, the words feeling strange in my mouth. She wasn't my mother—not really—yet her approval meant something to me nonetheless.
That night, as I practiced energy manipulation in the privacy of my bedroom, I reflected on the day's developments. The medical cover story would serve me well—explaining both the breathing techniques for energy suppression and any public manifestations of pain during adaptation phases. It wasn't ideal, but it created plausible deniability for my increasingly un-Issei-like behavior.
"A clever development," Ddraig commented as I focused on channeling small amounts of draconic energy through my fingertips, creating faint crimson trails in the darkened room. "Though human medicine will eventually become suspicious if you continue seeing specialists."
"I'll only need to maintain the fa?ade until school starts," I replied, watching the energy dissipate as I released control. "By then, I should have better mastery of suppression techniques."
"Perhaps. Your progress is remarkable for a new wielder, though far from complete." The dragon's voice carried centuries of experience. "The next phase of training should focus on combat applications, now that basic energy control is developing."
I nodded, already formulating plans. "The abandoned storage unit would work for combat training. Private enough that I can practice without witnesses."
"Wise. Though you'll need weapons to train with. This body lacks the muscle memory your original possessed."
That was true. While I had Andrew's knowledge of martial arts and combat techniques, Issei's body had never thrown a proper punch or kick. The disconnect between mental knowledge and physical execution remained a significant challenge.
"I'll start with basics," I decided. "Forms, stances, strikes. Then move to improvised weapons. I can't exactly purchase proper training gear without raising questions."
"The human female saw you during an adaptation episode," Ddraig reminded me. "The one with pink hair. She may become a complication."
Katase. I'd almost forgotten about her potential witness to my moment of weakness. "I'll monitor the situation. If she seems suspicious when school starts, I'll develop a cover story."
The next morning found me back at the storage unit, having told Issei's parents I was joining a summer martial arts program at a community center. The lie came easily, supported by the doctor's approval of "moderate exercise" despite my condition.
I began with karate basics, moving through forms I'd practiced thousands of times in my previous life. Issei's body felt awkward initially—the muscle memory wasn't there, and the proportions were different from Andrew's adult frame. But the enhanced strength and endurance from the draconic heart compensated for these limitations.
"Back straight, stance wider," I muttered to myself, adjusting my position as I executed a front kick. "Power from the hip, not just the leg."
Hour after hour, I drilled fundamentals. Punches, kicks, blocks, stances. Each repetition built new pathways between mind and muscle, gradually synchronizing Andrew's knowledge with Issei's physiology. By midday, sweat poured down my face, and my limbs trembled with exertion.
"This body is stronger than it looks," I observed, pausing for water. "The draconic heart significantly enhances basic physical capabilities."
"Your endurance is approximately triple that of a normal human teenager," Ddraig confirmed. "Though nowhere near what it will become with further transformations."
"One step at a time," I reminded him. "Mastering basics before advancing to more complex abilities."
After a short break, I moved to akido techniques—focusing on redirecting force rather than generating it. These required more finesse than raw power, presenting a different challenge for my enhanced physiology.
"It's about flow," I reminded myself, practicing a basic wrist lock and throw. "Using the opponent's momentum against them."
"Such techniques would prove effective against fallen angels," Ddraig observed. "Their overconfidence often leads to overcommitment in attacks."
He was right. In the anime, fallen angels like Raynare relied heavily on overwhelming power rather than tactical precision. A skilled practitioner of redirection techniques might exploit that tendency—if they survived the initial exchange.
Days turned into weeks as I established a training routine. Mornings for physical conditioning and martial arts, afternoons for energy control and suppression techniques, evenings for strategic planning and information gathering about the supernatural world through Ddraig's knowledge.
Three weeks after the heart transformation, I experienced another breakthrough during a particularly intense training session.
I was practicing with a metal pipe—an improvised weapon similar in weight and balance to a short sword—when another adaptation pain hit unexpectedly. I doubled over, the pipe clattering to the concrete as fire seemed to spread through my veins from the draconic heart.
"Don't fight it," Ddraig instructed, his voice cutting through the haze of pain. "This is different from previous adaptations. Your heart is attempting to channel power more efficiently."
Gritting my teeth, I forced myself to relax, to accept rather than resist the burning sensation. As I did, something shifted within my chest—a sensation like a lock clicking into place—and suddenly, power flowed more smoothly through my system.
I gasped as the pain transformed into something else entirely—a rush of energy that made my skin tingle and my vision sharpen. Without conscious thought, I reached for the fallen pipe, and as my fingers closed around it, crimson energy with emerald highlights flowed from my hand into the metal.
The pipe glowed with supernatural light, extending its effective length by several inches as the energy solidified around it like a blade of pure power.
"What is this?" I breathed, swinging the energized weapon experimentally. It cut through the air with a faint hum, leaving trails of light in its wake.
"Your first manifestation of external draconic energy," Ddraig explained, approval evident in his tone. "The ability to channel power through objects, enhancing their properties."
I stared at the glowing pipe in wonder. This was something the original Issei hadn't developed until much later in his journey—after becoming a devil and undergoing multiple power-ups.
"Why can I do this so soon?" I asked, maintaining the energy flow with surprising ease. "This doesn't match the original timeline of ability development."
"Your unique situation continues to create unexpected outcomes," the dragon replied. "The soul fusion and your conscious knowledge of combat applications are accelerating certain aspects of power development, while your human body limits others."
I practiced with the energized pipe until exhaustion forced me to stop, discovering that I could maintain the enhancement for nearly thirty minutes before needing to rest. The technique drained energy at a significant rate, but offered tactical advantages that could prove crucial in future confrontations.
By the time the sun set, I had developed rudimentary control over the energy extension, able to adjust its length and intensity with conscious focus. Not perfect, but promising—especially considering I was still human, without the advantages devil transformation had given the original Issei.
As I walked home that evening, muscles aching but spirit energized by the breakthrough, I spotted a familiar figure ahead on the path. Pink hair caught the setting sun as Katase jogged along the riverside park, seemingly engaged in her own summer training regimen.
For a moment, I considered avoiding her—changing direction or hanging back until she passed. But security training had taught me that sometimes the best defense was a controlled offense. Better to establish casual contact now than have her spreading rumors about my strange behavior when school resumed.
"Evening," I called as our paths naturally converged near a water fountain. Keeping my voice neutral, neither overly friendly nor dismissive.
She startled slightly, clearly not having noticed my approach. Recognition dawned in her eyes, followed immediately by wariness.
"Hyoudou," she acknowledged coolly. "I didn't know you used this park."
"Just started recently," I replied with a casual shrug. "Training for a martial arts program."
Her eyebrows rose skeptically. "You're doing martial arts? Since when?"
"People change," I said simply. "Decided to try something new this summer."
She studied me with unexpected intensity, her gaze lingering on my face. "You look different."
I maintained neutral expression, though inwardly I tensed. Had she noticed the subtle changes in my eyes? The slightly more defined musculature developing from weeks of intensive training?
"Just tired from training," I deflected. "What about you? Kendo practice doesn't stop for summer, I'm guessing?"
She seemed surprised by the normal conversation—the old Issei would have likely made some perverted comment about her athletic outfit.
"Tournament in September," she confirmed cautiously. "Have to keep in shape."
An awkward silence fell between us—two people with a history of antagonism suddenly engaged in civil conversation without the established scripts of pervert and enforcer.
"Well," I said finally, "good luck with your training. I should get home."
As I turned to leave, she called after me: "Hyoudou!"
I paused, glancing back.
"I saw you a few weeks ago," she said, hesitation in her voice. "Near the shopping district. You looked... sick. Like you were in pain."
So she had witnessed one of the adaptation episodes. I weighed my options quickly, deciding the medical cover story would serve here as well.
"Heart condition," I explained with a dismissive wave. "Nothing serious, but it acts up sometimes. Doctor says it's manageable."
"Heart condition," she repeated dubiously. "And they're letting you do martial arts?"
"Moderate exercise is actually good for it," I replied, the partial truth coming easily. "It's the breathing techniques that really help during episodes."
She didn't look entirely convinced, but nodded slowly. "That explains the weird breathing I've seen you doing sometimes."
I raised an eyebrow. "You've been watching me?"
A flush spread across her cheeks. "Not like that! Just... noticed. You've been acting strange all summer. Everyone's talking about it."
"Everyone?" I asked, genuinely curious what Kuoh's rumor mill had made of Issei's transformation.
"Well, mostly the kendo club," she admitted. "We noticed you haven't been peeping at all since summer started. Murayama thinks you got a girlfriend who straightened you out."
I chuckled despite myself. If only they knew how far from the truth that was.
"No girlfriend," I assured her. "Just... perspective change. Near-death experiences do that sometimes."
Her eyes widened. "Near-death? The heart thing is that serious?"
"It was, briefly," I acknowledged, seeing no harm in building sympathy that might be useful later. "Better now with treatment. But it makes you think about what matters."
She studied me with new interest, as if seeing me properly for the first time. "And what matters to Issei Hyoudou these days, if not peeping at girls?"
"Self-improvement," I replied honestly. "Being someone I can respect when I look in the mirror."
Something in my tone must have convinced her of my sincerity. She nodded slowly, a hint of approval in her expression that would have been unthinkable a few weeks earlier.
"Well... good luck with that," she said, surprising me with what appeared to be genuine sentiment. "And with the heart thing."
"Thanks," I replied, equally sincere. "Good luck with your tournament."
As I continued home, I reflected on the unexpected exchange. Small interactions like these were already altering the social landscape I would navigate when school resumed. The original Issei had been despised by most female students for his perverted antics, creating obstacles to potential allies beyond the Occult Research Club.
My different approach might open doors the original Issei never had access to—including possible human allies like the kendo club members, whose combat experience could prove valuable even against supernatural threats.
The final month of summer break saw accelerated progress in all aspects of my preparation. The draconic heart fully integrated with my human body, allowing for smoother energy distribution and fewer painful adaptation episodes. My martial skills developed rapidly, muscle memory finally beginning to align with mental knowledge.
Energy manipulation became increasingly intuitive—I could now channel power through weapons for extended periods without exhaustion, create short-range defensive barriers, and even execute limited ranged attacks by projecting concentrated energy. None of these abilities matched what the original Issei had eventually achieved with devil enhancement, but they represented capabilities far beyond normal human parameters.
Most importantly, I mastered basic energy suppression. While not perfect—intense emotions or physical strain could still cause leakage—I could now maintain a relatively normal energy signature that wouldn't immediately alert supernatural entities to my nature.
One week before school resumed, Ddraig confirmed my readiness.
"Your control is adequate for initial interaction with devils," he assessed as I completed a particularly complex suppression exercise. "They will sense something unusual about you, but nothing that immediately suggests the Red Dragon Emperor."
"And my combat capabilities?" I asked, practicing forms with the energized pipe that had become my primary training weapon.
"Sufficient to handle low-to-mid tier fallen angels in one-on-one confrontations," he replied thoughtfully. "Though multiple opponents or higher-tier entities would still overwhelm you without further transformation."
That aligned with my own assessment. I could likely handle someone like Raynare in her initial attack, but facing multiple fallen angels or someone like Kokabiel remained beyond my current capabilities.
"The timeline gives us some breathing room," I noted, setting aside the pipe. "Raynare doesn't approach until after school starts, and Asia doesn't arrive until weeks later. Time to continue developing while maintaining cover."
"A reasonable assessment," Ddraig agreed. "Though your foreknowledge remains your greatest advantage. Use it wisely."
I nodded, mentally reviewing the coming events as I'd gleaned them from the anime. Raynare's approach disguised as Yuuma Amano. The date ending in attempted murder. Rias's opportunistic resurrection. Asia's arrival and subsequent captivity. Each event presented opportunities to alter the timeline in ways that might improve outcomes without sacrificing strategic positioning.
"One thing at a time," I reminded myself. "First objective: survive the initial confrontation with Raynare without requiring resurrection."
"An objective that would have seemed impossible for an ordinary human," Ddraig observed. "Yet within reach for what you've become."
"And what have I become, exactly?" I asked, the question that had lingered throughout these weeks of transformation.
"Something new," the dragon replied thoughtfully. "Not fully human, not truly dragon. Not the original soul of this body, nor entirely the one who joined it. A unique existence forged through adversity and determination."
I considered this as I gathered my training gear, preparing to return home for the final week of preparation before school resumed.
"I can live with unique," I decided. "As long as 'alive' remains the operative word."
As the last days of summer break dwindled, I found myself standing before the gates of Kuoh Academy, surveying what would soon become my battlefield. The elegant architecture and manicured grounds betrayed nothing of the supernatural powers that controlled this territory—the devil heiresses who would soon take intense interest in my existence.
"The next phase begins," I murmured, touching the crimson amulet hidden beneath my shirt. Its warmth pulsed in rhythm with my draconic heart—a reminder of how far I'd come and how much further I had yet to go.
"Indeed," Ddraig agreed. "The world believes you human. Let them maintain that illusion as long as possible."
I nodded, turning away from the school gates. One week remained before I would walk through them officially, entering the domain of devils with a dragon's heart beating in my chest and a security officer's tactical mind guiding my actions.
Let them underestimate me. Let them see only Issei Hyoudou, reformed pervert with unusual potential. By the time they recognized the truth, the advantage would be mine.
"The Red Dragon Emperor awakens," I whispered, smiling slightly as I headed home for final preparations. "And this time, the story changes."