Gacha Harem King DXD What If: Esdeath (Patreon)

The throne room of the Hidden Castle stood silent… for once. No bickering, explosions or Nyaruko and Karura trying to assault him. 

At the center of the room, Issei took a breath, sweat prickling at his brow. He stood before the glowing interface, his finger hovering just inches away from the command. ‘Alright… calm down…’ He told himself, inhaling slowly. ‘It’s just another summon. Another girl. Please let it not be worse than Nyaruko…’ And with a single tap, the roulette wheel burst into existence once more, its clicking echoing like thunder through the throne room as Issei held his breath, excited about meeting a new beautiful girl, hoping that she gets along with everyone living here. 

The roulette wheel’s thunderous clicking slowed, each tick echoing like the beating of a drum. Issei could be seen leaning forward, eyes wide with anticipation and dread.

Until the glowing pointer crept to a halt and a message burned into existence.

[Roll ??: Esdeath has been summoned.]

A blinding dazzle of light erupted in the center of the throne room and Issei threw his arm up, shielding his eyes as wind howled outward from the summoning circle, whipping his clothes and rattling the fabric of the throne room.

When the light faded, a new figure stood. A tall, beautiful and young slender woman with long, light blue hair and blue eyes, wearing a General's apparel with long sleeves with buttons on the upper arms, a blue scarf on her neck and high-heeled boots and a peaked hat that had the crest on the front. She also has a tattoo on her chest.

Even without still, she radiated power and control. Her piercing blue eyes then locked onto him.

“...So,” Esdeath murmured. Her voice was a chilling silk, smooth and terrifyingly calm. “You are the one who summoned me… my fated husband?”

Issei gulped. ‘She’s hot. She’s REALLY hot with big oppai. So why do I feel like I’m about to die?’ The memory of his first meeting with Karura flashed through his mind, the immediate challenge, the clash of wills. He braced for the impact.

Before he could respond, Esdeath tilted her head, a predatory smile tugging at the corner of her lips. The temperature didn't just drop; it plummeted. A wave of pale blue frost exploded from her boots, racing across the floorboards in an instant. Ice crawled along the floors, climbed the pillars, froze the very air as a suffocating cold swallowed everything.

Issei, luckily thanks to Evangeline, knew what to do. Without hesitation, he reacted. Power and magic surged through his body as he released his energy, heat bursting outward in response. His skin flushed as his magic ignited, forcing warmth back into the space around him, resisting the encroaching cold.

Steam hissed violently where heat met ice. The two forces clashed for a brief moment. 

“Boosted Gear!” In a flash of crimson, the gauntlet materialized over his left arm and his power doubled instantly, heat flaring stronger, forcing the frost back another inch.

Then it all stopped as Esdeath’s eyes sharpened and a flicker of interest, excitement, joy and hunger flashed through her eyes.

“…Oh?” She could feel it, his power, raw, unrefined. But powerful. Strong enough to push her back, she could quickly tell that he wasn’t trying and a part of her really wanted to push him but this was enough for now. A slow, pleased smile spread across her lips. “…Good.” The frost receded slightly. “I’ve decided.”

Before Issei could react, the space between them vanished. She was there in a blur of white and blue. A gloved hand clamped firmly onto his chin, tilting his head back with effortless authority. Her gaze bore into his, dominant and utterly possessive. “You’ll now belong to me.” She declared, her tone leaving no room for negotiation.

“EH?!” His brain short-circuited instantly. “W-WAIT—WHAT?!”

A cheerful, almost mocking chime rang inside his head, accompanied by a scrolling text box:

[Summoning Complete: Esdeath. Love Meter: 100%]

‘WHY IS IT ALREADY AT THE MAX?!’ Issei screamed internally, his soul practically leaving his body. ‘I HAVEN’T EVEN INTRODUCED MYSELF YET!’

—----------------------------------

After the situation calmed down, Issei and Esdeath introduced themselves. With Issei explaining several things about their living arrangements. It didn’t take long for things to go wrong, very wrong.

The air in the throne room didn't just chill; it turned brittle, as if the oxygen itself were being crushed under the weight of her presence.

"I will not tolerate any rivals," Esdeath stated. Her voice was flat, devoid of heat, carrying the terrifying inertia of an absolute decree. She crossed her arms beneath her bountiful chest, that Issei continued to stare, Esdeath didn’t bother to stop and instead relished in the attention, her narrowed eyes tracking Issei like a predator marking its territory. "Any woman you summon after this moment and before will be rejected."

Issei felt a cold sweat prickle his spine. "…Rejected?"

"Yes," She replied simply, as if discussing the weather. "Disposed of, if necessary. Only the strong deserve to stand at your side, and I am the strongest."

"EHHHHHH?! WAIT, WAIT—HOLD ON!" Issei’s hands flew up in a frantic blur, his heart doing a panicked somersault. "That’s not how this works! You’re not the first! I’ve already summoned a bunch of people!"

The silence that followed was heavy, suffocating.

Esdeath didn't move. She didn't blink. She simply stared at him, her blue eyes turning into shards of polished glass. "…Explain."

Suddenly, the throne room felt like a military tribunal. Issei felt less like a King and more like a fresh recruit awaiting a court-martial. "W-well—there’s Nyaruko, and Kaguya, and Evangeline, and… uh, quite a few more," He trailed off, his voice losing its strength as her expression remained unreadable.

A long, agonizing pause stretched between them.

"…They do not matter," she said with a dismissive flick of her gloved hand. Her tone was final, cutting through his explanation like a guillotine.

Issei’s stomach dropped. This wasn't just the usual chaotic bickering he was used to with the others.This was cold, calculated, and lethal. 'She’s serious. She’s actually going to hurt and attack them.' His fists clenched at his sides, his fear being overtaken by a desperate need to protect the home he’d built. "No… I can't let that happen."

"Look," He said, forcing his voice to stay steady despite the frost literally creeping toward his boots again. "You’re going to have to find a way to get along with them. They’re important to me."

"…Important?" She repeated the word as if it were a foreign concept, her gaze sharpening with a flicker of something, was it jealousy or curiosity?

"Yeah," Issei said, his resolve hardening. "They’re my family. All of them."

That gave her pause, but the reprieve was momentary. A thin, dangerous smile curled her lips, the look of a general who had just found a new campaign to wage. "Then I shall determine their worth myself."

Issei’s heart skipped a beat. "Wait—what does that—"

But the warning died in his throat. In a flash of blue and white, Esdeath vanished from his immediate reach, the frost on the floor shattering like glass under the sudden shift in her killing intent.

"If they are 'family,' they must be capable of surviving me," She whispered, her voice echoing from the doorway. "Let us see if they are worth the space they occupy in your heart."

—----------------------

The atmosphere in the main hall didn't just change; it curdled.

The moment Esdeath’s boots clicked against the marble of the grand foyer, the casual domesticity of the Hidden Castle vanished, replaced by the jagged tension of a powder keg.

“Oh? A new face?” Nyaruko’s voice chirped, her long silver hair bouncing as she looked up from a gaming handheld. Then, her head tilted. The playful spark in her emerald eyes cooled into something ancient and predatory. “…Oho? This one smells like trouble.”

Kaguya’s eyes narrowed into slivers of molten gold, her posture shifting from relaxed to regal in a heartbeat. Evangeline didn't even bother to stand; she simply leaned back in her ornate chair, a weary, annoyed sigh escaping her lips. Beside her, Shiraori remained a silent statue, her head tilting with a mechanical, haunting precision as her multiple pupils tracked the newcomer.

The air thrummed. It was the silent communication of monsters recognizing a peer.

Esdeath’s gaze swept across the room, her icy blue eyes performing a cold, clinical triage of every woman present. After a heartbeat of calculation, she spoke. The word dropped like a blade. “...Weak.”

The reaction was instantaneous. Nyaruko’s cheerful smile didn't fade, but it gained a sharp, jagged edge that promised madness. Kaguya’s aura flared, the very shadows of the room lengthening and twisting. Evangeline’s eyes gleamed with the crimson light of a true Shinso.

Then, the floor vanished under a tide of white.

Without a word of further warning, Esdeath struck. A forest of jagged, skyscraper-sized ice spears erupted from the ground, surging toward the group with enough force to level a mountain.

But they never hit.

The air groaned under a sudden, multi-layered defense. Shiraori’s invisible threads snared the lead spikes, halting them mid-flight. Kaguya’s spatial barriers flickered into existence, causing the ice to shatter against thin air. Evangeline’s runic circles glowed a deep, violet hue, absorbing the kinetic energy before it could even rattle her teacup.

Silence reclaimed the hall, heavy, oppressive, and thick with the scent of ozone and frost.

Shiraori lowered her hand with agonizing slowness, her many crimson eyes locked onto Esdeath with a stare that transcended human understanding. Kaguya snapped her fan open, the sound echoing like a gunshot. Her expression was no longer that of a companion, but of a goddess looking down upon a mortal.

“You are new,” Evangeline said lazily, her voice dripping with bored condescension. “So I will overlook that… exactly once.”

Kaguya’s voice cut in, sharp and absolute, pressing down on the room like a divine decree. “But understand this clearly, General. You are not the only one here who has looked upon the face of death and laughed.”

Nyaruko’s grin widened, her crowbar resting casually against her shoulder as her eyes glowed with a chaotic, eldritch excitement. “Welcome to the family, Newbie~! Hope you like bruises!”

Esdeath stood amidst the shattered remnants of her own ice, perfectly still. Her silence stretched out, taut and dangerous. Then, a slow, thrilled smile spread across her face, not the smile of a general, but the smile of a woman who had finally found a playground worthy of her.

“How delightful,” She whispered, her eyes gleaming with a manic, joyous light. “It seems I won't be bored after all. This will be very interesting.”

In the background, Issei stood paralyzed, a single bead of sweat rolling down his temple as he watched the literal and metaphorical temperature of the room reach a boiling point. “...I’m so screwed,” he whimpered to the empty air. “I am so, so screwed.”

—-------------------

Morning, Day ?? — Hyoudou Hidden Castle, Dojo

The air in the dojo felt cold and sharp as a thin, crystalline mist rolled off Esdeath’s silhouette, frost blooming in intricate, jagged patterns wherever her boots touched the floor. She stood dead center, arms crossed over her tactical bustier, her long azure hair swaying in a draft that shouldn't have existed indoors. “…You’re late.” 

Issei stood in the doorway. His hair was a bird’s nest, one sleeve of his jacket was pushed up higher than the other, and he was mid-yawn. “I literally just woke up,” He groaned, rubbing a bleary eye. “The sun isn't even fully up yet, Esdeath...”

Esdeath tilted her head with the cold precision of a hawk. “That is irrelevant. A warrior and my husband must be ready to kill or be killed at any moment.”

Issei blinked, the sleepiness finally beginning to evaporate under the sheer weight of her intensity. “…I knew I should’ve stayed in bed.”

“Too late.” She didn't reach for a weapon. She simply flicked her wrist.

The temperature plummeted into the negatives instantly. Issei’s survival instincts, forged in the fires of countless brawls, screamed a warning. “WAIT—!”

He threw himself backward just as a six-foot spire of enchanted ice erupted from the floorboards, shattering the wood with the force of a landmine. Had he been a second slower, he’d have been skewered.

“ARE YOU SERIOUS?!” He roared, scrambling to find his footing on the now-slick floor.

Esdeath didn’t offer an apology. Instead, a terrifyingly beautiful smile spread across her lips—the look of a woman who truly loved her work. “Defend yourself, Issei.” She raised both hands. A barrage of frozen spears, sharper than diamond and faster than bullets, shrieked through the air.

“BOOSTED GEAR!” The red gauntlet materialized with a mechanical snarl, the green jewel at its center pulsing with a rhythmic, draconic light.

[BOOST!]

The surge of power hit his veins as Issei lunged forward, weaving through the icy rain. He moved in a blur of red and gold, fragments of ice whistling past his ears and slicing into the walls behind him.

‘She’s not holding back even a little bit!’ He punched a direct hit from a jagged pillar, the impact sending a shockwave of frozen shrapnel across the room. The cold bit into his skin, numbing his knuckles. 

He pushed off the ground to close the gap, but the floor turned into a frictionless sheet of ice beneath him. His lead foot slipped, his momentum betrayed him, and a massive wall of frost slammed into his chest like a freight train.

“GAH—!” Issei skidded twenty feet across the frozen dojo, his clothes stiffening with rime. He groaned, shaking the stars from his vision as he pushed himself up onto one knee. “…Okay, seriously, what the hell is this supposed to be? Is this how you say good morning?!”

Esdeath lowered her hand slowly, the mist around her swirling lazily. “…This is a date.”

Issei stared at her, his jaw dropping. “…No. No, it is absolutely not.”

“Yes,” She countered firmly. “It is.”

“You’re trying to put a hole through my chest!”

“I am not.” She stepped toward him, the rhythmic click-clack of her high-heeled boots echoing through the silent room. “I am strengthening you. There is no greater intimacy than the clashing of wills.”

Issei wiped a smear of frost from his cheek, glaring at her with genuine exasperation. “By stabbing me?! Most girls want flowers, Esdeath! Maybe a movie!”

“If you cannot survive this,” She replied, her voice dropping into a tone of chilling logic, “you will eventually die to something weaker than me. And that is an outcome I will not permit.”

Issei started to snap back, but the words died in his throat. He looked at her and noticed how her hand was clenched tight at her side, her knuckles white. There was no mockery in her eyes, only a fierce, possessive desperation.

The anger in his chest flickered out, replaced by a strange, heavy realization. ‘...Man. This is actually her version of caring, isn't it? She's terrified of losing me.’ He scratched his neck awkwardly, exhaling a cloud of silver breath. “…You know… most people just say ‘be careful’ or ‘I love you’ or something.”

“…That is not good enough,” She murmured. “Words alone will not be enough to protect you. Strength does.”

“…Yeah, figures.” Issei stood up straight, rolling his shoulders until his joints popped and he got into a fighting stance. “…Alright. Fine.”

Esdeath’s eyes sharpened, a spark of hope or perhaps just bloodlust, igniting in her gaze. “…You will continue?”

“Yeah,” Issei said, his grin returning, albeit a bit tired.

[BOOST!]

The power flared brighter this time, the heat from the Boosted Gear actually beginning to melt the frost on his shoulders. “But after this we’re doing something else, too.

Esdeath paused, her interest piqued. “…Explain.”

He pointed his gauntlet directly at her and gave her his boyish grin. “We train and I’ll get stronger. But after this? We’re going on a proper date. Just the two of us.”

The silence stretched. Esdeath actually blinked, the concept seemingly harder to process than a complex military maneuver. “A... Date? Like the civilians do?”

“Yeah,” he said. “Normal couple stuff. Food. Walking. Maybe holding hands if you’re good.”

She stared at him, her mind clearly racing, a flash of eagerness and desire entered her eyes but she quickly turned a bit bashful. “…That is technically unnecessary for combat readiness.”

“Too bad,” Issei shot back, his grin widening into a challenge. “It’s part of the deal. You want me to be the strongest? Then you have to give me something to fight for.”

Another long pause. Then, the oppressive weight of her aura shifted. It didn't disappear, but the jagged edges smoothed out. The cold remained, but it felt... focused. Controlled.

“…Very well.” She raised her hand again, but this time, the ice formed a delicate, crystalline rapier in her grip. “Show me this strength of yours, Issei. If you impress me... I shall allow this 'date'.”

Issei braced himself, the red dragon’s light roaring to life. “Gladly! Don't complain when I melt all your hard work!”

—-----------------------------------------

Later, Kuoh, Outdoor Dinner

The afternoon sun hung low, casting long, amber shadows across the building of Kuoh. Issei sat slumped at a small table, his chest still heaving. Faint wisps of steam rose from his damp shirt as his body temperature finally began to normalize after hours of exertion.

“I can’t… feel my legs…” He wheezed, his head lolling back against the chair. “I think my soul actually left my body somewhere around the three-hour mark.”

Across from him, Esdeath sat in casual clothes carefully prepared by Shiraori in terrifyingly perfect composure. Not a single strand of her ice-blue hair was out of place; her blue blouse that showed a bit of her cleavage was as crisp and pristine. She leaned back, crossing one long stocking leg over the other, her gaze never leaving him. “I can tell that you have improved,” She stated.

“Yeah,” Issei muttered, wiping a lingering bead of melted frost from his temple. “Funny how ‘not dying’ is such a great motivator. My survival instincts have never been more awake.”

A large, steaming plate of local specialty skewers sat on the table between them—honey-glazed meat and roasted vegetables that smelled heavenly in the cool evening air.

Esdeath leaned forward, picking up a skewer with a delicate, gloved hand. She studied the charred meat. “…And this,” She said, her voice dropping into that thoughtful, silk-smooth register. “This is part of the ‘date’?”

“Yeah…” Issei watched her, a bit of his usual energy returning as he saw her genuine confusion. “The part where we don't try to impale each other. We just… eat. And talk. See? No ice spears. No explosions. Just us.”

She took a slow, methodical bite. Her eyes widened almost imperceptibly as she chewed. After a moment of silence, she swallowed and nodded slowly.

“…It is good,” she admitted. A small, rare softness touched the corners of her mouth, a ghost of a smile that made her look less like a living weapon and more like the woman Issei knew was hidden underneath the armor.

Issei smirked weakly, his heart fluttering just a little. “Told you. Not everything has to be a battlefield, Esdeath.”

The bustle of the town carried on around them, the sound of distant laughter, the clinking of glasses, and the warm hum of people living their lives.

Esdeath set the skewer down and looked him directly in the eyes. The possessiveness was still there, burning like a cold blue flame, but it was tempered by something new. “…We will do this again,” she declared.

Issei let out a long, theatrical groan, burying his face in his hands. “…Of course we will. My life is a series of beautiful women trying to kill me with kindness or actual ice.” But despite the exhaustion, despite the lingering chill in his bones, and despite the fact that he knew Nyaruko was probably going to tackle him the moment he stepped back into the castle… he smiled.

—--------------------------------

Late Night, Hyoudou Hidden Castle, Issei’s Room

The church had finally surrendered to the night. For a miraculous hour, the chaos had subsided. No eldritch shrieks from Nyaruko, no shattering furniture from Karura’s "friendly" sparring, and no ominous chanting from the basement. Just the low, rhythmic hum of the castle’s magical core.

Issei lay sprawled across his bed, staring at the dark patterns on the ceiling. Every muscle in his body felt like it had been tenderized by a gravity hammer. ‘Man… today was a marathon,’ he thought, a wince crossing his face as he shifted. Training with Evangeline had been a masterclass in pain. Yet, a small, tired smile tugged at his lips. He was stronger than he was yesterday. He was surviving.

Then—click. The door to his room started opening. Issei didn't even bother to sit up. He just sighed in bliss into his pillow wondering who he will sleep with tonight but the moment he felt the chill in the room he instantly knew who it was. “…You didn’t knock, Esdeath.”

“A general does not ask permission to enter her own territory.”

Issei groaned and rolled over. The sight that met him effectively short-circuited his remaining brain cells. Esdeath stood in the doorway, the moonlight catching the shimmering blue silk of her lingerie. It was minimal, elegant, and utterly devastating. Her long, ice-blue hair spilled over her shoulders like a frozen waterfall, and her gaze was locked onto him with predatory focus.

“…What do you need, Esdeath?”

She didn't answer with words. She marched forward, each step deliberate, her heels silent on the rug until she loomed over the bedside. “In accordance with the rotation established by the others, tonight is my designated time for 'intimacy'.”

Issei blinked, his face heating up. “…Yeah? I mean, yesterday was Karura, so—”

“—And now, we shall sleep.”

Before Issei could process the "how" or the "where," the mattress groaned. A sudden, irresistible force surged over him.

“WOAH—HEY—!”

In one fluid, maneuver, Esdeath swept him into her arms and fell back against the pillows, dragging him into a crushing embrace. Issei froze. His face was pressed firmly into blue silk and her bountiful chest. “I… I can’t move my arms.”

“Good,” she murmured, her breath cool against his neck. “Security is paramount.”

“ESDEATH, I CAN’T BREATHE—!”

Her grip tightened and pushed him further into her breasts. To her, this was a light hug; to Issei, it was a hydraulic press.

“…Stop struggling, Issei. I want to feel you, right next to me.”

He tried to wiggle an inch of space, but it was like trying to fight a glacier. ‘Is this the end?’ he wondered frantically. ‘Once again I'm about to be crushed to death by Oppai. There are worse ways to go, but I’d like to actually live to see tomorrow!’

“…Esdeath,” he wheezed.

“Yes?”

“…You’re actually going to kill your ‘fated husband’.”

She paused. The physical pressure didn't vanish, but the intent shifted. Her arms loosened by a fraction of a millimeter. “…Explain.”

“I NEED OXYGEN TO STAY ALIVE!”

“…Ah.”

She adjusted her hold, shifting him so his face was no longer buried. She tucked his head under her chin, her legs intertwining with his to ensure he was completely anchored. “…Better?”

Issei took a ragged, desperate lungful of air. “…Barely. I think I heard my ribs file a formal complaint.”

The room fell into a heavy, resonant silence. The cold aura that usually radiated from her was gone, replaced by a surprising, steady warmth.  A long pause followed. The dominant general seemed to recede, replaced by something quieter. Her grip shifted as her fingers curled slightly into his shirt.

“…You are warm,” she said, her voice barely a breath. “…It is… pleasant. It calms my bloodlust.”

That caught him completely off guard. He tilted his head, looking up at her. Her eyes were closed, her expression smoothed into a rare, serene calm. In the dim light, the bloodthirsty sadistic general looked vulnerable. Just a girl who spent her life in the cold, finally finding a hearth.

“…You could’ve just said you wanted to cuddle,” Issei muttered, his heart softening.

“…Unnecessary. I have achieved the objective.”

“…Right. Classic you.” He hesitated, then carefully, he let his weight settle against her. “…You know… you don’t have to trap me. I’m not a runner.”

“…I must.”

“…Why?”

Another silence stretched out, thick and honest.

“…Because things that are not held,” She whispered, “have a habit of disappearing in the night.”

Issei felt a pang in his chest. He shifted again, and this time, she didn't fight him. He draped an arm over her waist, matching her hold. “…There. See? I’m still here. I’m not going anywhere, Esdeath.”

Her grip loosened further. The "trap" became a simple embrace. Her breathing slowed, syncing with his. “I guess this is acceptable,” she breathed.

Minutes ticked by. The phantom pains of his training began to fade into the warmth of the bed. Issei’s eyelids grew heavy, the scent of winter lilies and silk lulling him toward sleep. ‘...Maybe she’s not so terrifying after all,’ he thought drowsily. ‘Just a little... intense.’

“…We will perform this ritual every night,” she murmured into his hair.

Issei’s eyes snapped wide open. “…Wait—every night? What about the rotation? What about Nyaruko?!”

The grip tightened instantly, locking him back into place with the strength of ten men. “…Sleep, Issei. I have already annexed the schedule.”

“…I regret everything…” Issei whimpered, though he didn't actually try to get away.

Done, this is going to be a series of oneshots that show scenes of the various girls that Issei summons. Give me your opinion, who do you want next, give me scenarios of Issei spending time with those girls. I may return to write more of Esdeath and Issei, if I think of anything else.