Chapter 1: The Emperor Awakens
The first thing the new soul felt was not pain, nor confusion, but absolute clarity.
Darkness had swallowed him in his previous life — a mundane existence cut short by an unremarkable accident. One moment he was crossing a busy street, the next, nothing. Then came the voice, cold and mechanical, echoing through an endless void.
**"Suitable vessel located. Reincarnation protocol initiated. Transferring consciousness to Issei Hyoudou — High School DxD world. Activating Fate Thief System."**
When his eyes snapped open, he was lying in a simple bed inside a modest Japanese bedroom. Posters of anime girls adorned the walls, a familiar sight from the memories that now flooded his mind. But they weren't *his* memories. They belonged to the original owner of this body — a weak, perverted high school boy who dreamed of harems but achieved nothing.
He sat up slowly, flexing his fingers. The body felt... adequate. Athletic enough for a teenager, with hidden potential locked inside the Boosted Gear. But the real power surged through his veins like liquid fire — the **Fate Thief System**.
A translucent blue screen materialized in his vision, visible only to him.
**[Fate Thief System Activated]**
**Host: Issei Hyoudou (Reincarnated Emperor)**
**Current Level: 1**
**EXP: 0 / 500**
**Core Ability: Fate Theft — Steal destinies, loyalties, affections, and powers from canon paths.**
**Warning: The original soul residue is fading. In time, only the Emperor remains.**
A cold smile curved his lips. "So this is the world of devils, angels, and dragons. The canon where Issei Hyoudou becomes a hero through sheer luck and friendship. Pathetic."
He stood and walked to the mirror. The reflection showed the same messy brown hair, the same face, but the eyes were different now — sharp, calculating, glowing faintly with crimson ambition. No more drooling over every girl like a fool. From this moment, every beauty in this universe would be a prize to claim, not a distant dream.
**Main Quest Issued: First Conquest**
**Objective: Claim Rias Gremory completely — her heart, body, and loyalty. Erase the original Issei's weak influence from her path.**
**Reward: Level Up to 2, +10 to all Stats, Unlock 'Charm Theft' skill, Enhanced Boosted Gear access.**
**Failure Penalty: None (Emperors do not fail).**
**Time Limit: 7 days.**
He chuckled lowly. "Seven days? I'll do it tonight."
A knock sounded at the door downstairs. The voice that followed was elegant, commanding, and unmistakably familiar.
"Issei? Are you awake? I came to check on you after yesterday's... incident."
Rias Gremory.
The memories surged: the original Issei had been killed by a fallen angel and reincarnated as a devil by this very woman. She saw him as a cute, perverted underling with potential. In the canon, she would slowly warm to him through battles and shared hardships.
Not anymore.
He descended the stairs with measured steps, his posture straighter than the original Issei ever managed. When he opened the door, Rias stood there in her Kuoh Academy uniform, crimson hair cascading like blood-red silk, blue-green eyes scanning him with mild concern.
She was stunning — tall, curvaceous, radiating demonic power and noble grace. The kind of woman who could command legions yet carried an underlying loneliness from her arranged engagement.
"Issei, you look... different," she said, tilting her head. "Are you feeling alright? The reincarnation process can be disorienting."
He met her gaze directly, no nervous stuttering, no blushing. "I'm better than alright, Buchou."
The honorific rolled off his tongue with subtle authority. Rias blinked, caught off guard by the steady confidence in his voice. The original Issei would have been stammering about her breasts by now.
"Come in," he said, stepping aside. "We should talk."
Rias entered, her presence filling the small living room. She sat gracefully on the couch while he remained standing, leaning against the wall with crossed arms. The power dynamic had already shifted, though she didn't realize it yet.
"I wanted to explain more about your new life as a devil," she began, launching into the standard speech about the Gremory peerage, the Rating Games, and the supernatural world. Her voice was calm and instructional, treating him like a promising but naive recruit.
He listened patiently, absorbing every detail. The system helpfully overlaid notes in his vision:
**[Rias Gremory — Current Affection: Neutral (Canon Path Active)]**
**[Loyalty to Original Issei: Low but Building]**
**[Engagement Threat: Riser Phenex — High Destiny Interference]**
When she finished, silence fell. Rias waited for his usual enthusiastic questions or perverted comments. Instead, he spoke with quiet intensity.
"Buchou... Rias. You've given me a second chance at life. For that, I'm grateful. But I won't be the weak pawn you expect."
Her eyes widened slightly. "What do you mean?"
He pushed off the wall and approached slowly, stopping just close enough that she had to look up at him. "The old Issei is gone. In his place is someone who understands power. Real power. Not borrowed from friendship or luck, but taken. Stolen from fate itself."
A faint crimson glow flickered in his eyes. The system responded:
**[Fate Thief System: Minor Fate Scan Complete]**
**Rias Gremory's Canon Destiny: Become High-Class Devil, marry Riser Phenex against her will, slowly develop feelings for Issei through shared battles.**
**Opportunity Detected: Steal her loyalty early. Disrupt engagement path.**
Rias stood up, her demonic aura flaring instinctively at the change in his demeanor. "Issei, if this is some kind of joke—"
"It's not." He reached out and gently but firmly took her hand. The contact sent a spark through both of them. For her, it felt like a sudden pull — warm, commanding, impossible to ignore. For him, the system chimed:
**[Initiating Minor Fate Theft: Affection Thread]**
**Progress: 8%**
She didn't pull away. Instead, confusion mixed with an unfamiliar warmth spread across her cheeks. "Your eyes... they're different. Stronger."
"Because I see clearly now," he replied, his voice low and steady. "You deserve more than an arranged marriage to that peacock Riser. You deserve someone who will claim you, protect you, and build an empire at your side. Not as equals in weakness, but as Emperor and Queen."
The words hung in the air. In any normal scenario, Rias would have laughed or scolded him for overstepping. But something in his tone — absolute certainty, backed by the invisible threads of the system — made her pause. Her heart beat faster. The original Issei's clumsy charm was gone, replaced by raw, magnetic dominance.
"I... don't know what happened to you," she whispered, yet she didn't step back. "But this isn't the Issei I reincarnated."
"Good." He leaned closer, his free hand brushing a strand of crimson hair behind her ear. "The weak version fades today. Let me show you what the new one can offer."
The tension thickened. Rias's breathing grew slightly uneven. Her noble pride warred with the strange compulsion to listen, to yield just a little. The system continued its subtle work, stealing small threads of her destined resistance.
**Quest Progress: 15%**
He didn't rush. Instead, he guided her back to the couch, sitting beside her — close, but not overwhelming. They talked for hours. He asked intelligent questions about devil society, her family, the Rating Games. He offered insights that surprised her: strategic observations about peerage dynamics, ways to counter political pressures from her brother Sirzechs, even subtle hints at breaking her engagement without direct confrontation.
Rias found herself opening up more than she intended. She spoke of her loneliness, the weight of her name, the frustration of being treated as a political tool. In the canon, these conversations would happen gradually over many adventures. Here, under the influence of the Fate Thief, they flowed naturally — accelerated.
As evening fell, the atmosphere shifted again. The room grew quieter. Rias glanced at him, her usual composure cracking.
"Issei... why do I feel like I've known this side of you forever?"
He smiled — not the lecherous grin of old, but the confident smirk of an emperor surveying his first conquest. "Because fate is changing. And I'm the one rewriting it."
He cupped her cheek gently. She didn't resist. The system flashed:
**[Affection Thread Stolen: 42%]**
**[Loyalty Shifting from Canon Path]**
Their first kiss was slow, deliberate. Rias's eyes fluttered shut as she leaned into it, surprised by the intensity and control behind it. No clumsy fumbling — only steady dominance that made her demonic power respond with a thrill she hadn't expected. Her hands rested on his chest, feeling the heartbeat that no longer belonged to the old Issei.
When they parted, her cheeks were flushed, lips slightly parted. "This... is dangerous."
"Only for those who stand in my way," he replied. "Including the old version of myself."
The night deepened. He led her upstairs with quiet command, never forcing, but guiding with unshakeable confidence. In the bedroom, under soft lighting, the claiming began in earnest.
Clothes were shed with deliberate care. Rias, the proud heiress of Gremory, found herself yielding step by step. His touches were firm yet calculated, focusing on her responses, learning what made her gasp, what made her crimson hair spill across the sheets like a banner of surrender. He whispered promises of power, of a future where she stood at the pinnacle beside him — not as a tool, but as his chosen queen.
The system worked silently in the background:
**[Major Fate Theft in Progress]**
**Rias Gremory's Heart: 68% Claimed**
**Body and Loyalty: Progress Accelerating**
There was no vulgar frenzy, only controlled intensity that left her breathless and wanting more. She arched beneath him, her nails digging into his shoulders as waves of pleasure mixed with a profound sense of being *chosen*. The original Issei's shadow in her mind grew fainter with every shared breath, every whispered word of domination and ambition.
When release came for both, it was powerful and synchronized. Rias clung to him, her body trembling, eyes half-lidded with newfound devotion.
"Issei..." she murmured, voice husky. "What have you done to me?"
"Only the beginning," he answered, stroking her hair. "You're mine now, Rias. Not because of some Rating Game or family obligation. Because I stole that destiny from the weak path."
She smiled faintly, a mix of exhaustion and satisfaction. For the first time in her life, the weight of her engagement felt distant, irrelevant. In its place bloomed loyalty to this new, unstoppable version of her servant.
As she drifted into a light sleep beside him, the system chimed triumphantly.
**[Main Quest: First Conquest — 92% Complete]**
**EXP Gained: 480 / 500**
**Additional Bonus: Partial 'Charm Theft' Unlocked — Passive increase in attraction from targets.**
He lay there, staring at the ceiling, one arm around the crimson-haired devil who now carried his mark on her fate.
"Level up soon," he whispered to himself. "Then the real conquest begins. Akeno, Asia, Xenovia, Koneko... every beauty in this world. The fallen angels, the angels themselves if they prove worthy. Riser? He'll be the first example of what happens to those who lose what I claim."
Dawn approached. The Emperor had awakened, and the DxD universe would never be the same.
**[Chapter End Teaser]**
The next morning, a new notification awaited:
**Side Quest Unlocked: Disrupt the Phenex Engagement Announcement.**
**Reward: Massive EXP, New Skill — Destiny Sever.**
But shadows stirred elsewhere. A fallen angel sensed the shift in demonic energy around Kuoh Academy. And deep within the Boosted Gear, Ddraig stirred, confused by the new soul commanding his power.
How far would the Fate Thief go before the supernatural world noticed the emperor in their midst?