Fire engulfed everything, and Harry embraced it. It flowed through his body, lighting up his veins and instantly incinerating the shriveled sliver of Riddle's soul that had resided in his scar. The fiendfyre now leapt to his command, and he changed its purpose. Harry did not want to merely destroy- after all. He wanted to remake the world. That would require some destruction, yes, but it would require creation too. To have life you needed death, or else the world would become stagnant. To have death you needed life, for without life death was meaningless. Death was an integral and inescapable part of the world, but her counterpart was just as necessary- rebirth.
He sent phoenix fire forth and called Wanda and Carol to him. They appeared at his side. "Harry…" Carol gasped, staring at him. "You're… you're…"
"You know what you need to do." Harry said. Wanda nodded; her eyes wide as she looked at him.
The flames receded, but Harry still felt the inferno burning within him. It felt unquenchable- a mindless primeval power. Carol still stared at him, and Harry looked down at his hands. He realized what had struck her- his hands were glowing. The light seemed to shine from inside his body, flickering on his skin like a candle.
There was no time to dwell on it. Wanda had knelt on the floor and closed her eyes in concentration. Her chest began to burn with the red of her magic, it spread down her arms and ignited on her palms. Her magic burst out, expanding onto the floor and spreading through the air. Harry felt it overtake him as a ripple, and he didn't fight it, letting himself be enveloped by her world. There was a moment of disorientation, like that first time stepping through the barrier to Platform 9¾. The Room of Requirement reformed itself, appearing as Harry remembered it from his school days. The sense of malice that had emanated from the walls of the castle when Voldemort had been inhabiting it was gone. This was the Hex, this was Wanda's domain.
Wanda didn't waste time. She looked at Harry and her eyes flashed. A light glimmered in the air above her palm and the Time Stone appeared, floating in the air. Harry flicked his finger, sending the stone streaking into his staff, where it melded into the metal. The stone's power surged. It was endless yet ever changing, like a kaleidoscope of possibility. But this at least was a familiar power, one that he had recognized stirring within him since he'd awakened in this world, and that helped him keep it at bay.
The door disintegrated as an impact shook the room. A shadow stood at the threshold, separated from them by a wall of red static. Wanda winced. "She's here." She hissed.
"Keep going." Harry said. "Carol."
"On it."
Wanda next produced the Space Stone. Her face screwed up as she tried to fight Death's advance. The shadow pushed into the room, the barrier of her Hex denting and deforming despite Wanda's efforts. Carol unleashed her full power on the shadow, showering the room in blinding light. The stacks of books and furniture were blasted to each side, aged parchment blowing in the wind.
Harry merged the Space Stone with the staff, its power, vast and fathomless, churned through his body, but they couldn't slow down. Wanda produced Reality next. Harry imbued his staff with it and found that it was familiar. It felt like magic, terrifying and power in its capability, encompassing everything both marvelous and terrible that he'd known magic to do.
Tears were streaming down Wanda's face as she pushed herself further than she ever had before- twin titanic struggles, each alone more than he could ever ask of her. Yet she pushed on and gave him the final stone- the Mind Stone, the source of her own power. Harry swung his staff and felt a shift when it collided with the final infinity stone. The stones lined his staff now, embedded evenly along its length, and its metal burned hot. The power that surged through it- and through Harry- was overwhelming. It expanded and shifted and churned endlessly, impossible to pin down, predict, or fathom. Harry couldn't master this power, not truly, but he could withstand it.
Carol shouted, and he snapped back to reality. The light had faded, and Harry saw Death's hand rapped around Carol's arm. He didn't need to think. He appeared in front of Death with a burst of fire and slammed his staff against the floor. All six infinity stones ignited. "No." She gasped, reeling back from the power that emanated from him in waves. He had the universe at his fingertips, and with the power of the phoenix, he had the ability to remake it.
He had spent so much time worrying about the impossible choices he might have to make. He had worried that he'd have to choose between his two worlds, his two families. Worse, he'd feared that he'd ultimately have to sacrifice himself, forfeiting Lily and T'Chone's existence. Now, he could see the truth. He didn't have to choose, he wouldn't. The merger between the universes had already happened. He could feel this world, how it was composed of sharp, shattered pieces that grated against each other unnaturally. What he needed to do was reforge it. For that, he needed a fire, and he certainly had that.
Harry channeled the power of the phoenix through his staff, into the gems. The stones wove through the universe, their power anchoring it, acting as both foundation and glue. Pheonix fire burned through the world, through all of time and space. It touched the minds and souls of every being. Its power remade reality, fusing its broken pieces into a harmonious whole. None of this he could visualize properly, these things came to him the way one remembered a dream.
He found himself in this tapestry, a string of fate that weaved through it. A bundle of threads were tied around his- Natasha, Ginny, Wanda, and the rest. His heart swelled when he felt Lily and T'Chone, and it stuttered when he found more threads calling to him- more children in his future. He couldn't see how long his life would last. It was still uncertain, everything in the tapestry had a degree of uncertainty, the product of free will, luck and circumstance.
There was, however, a thread that had been cast adrift. He reached his mind out and cradled it- it was Septimius. There was no place for a child of Lily Evans and Severus Snape in this world, but that didn't mean there wasn't room for Septimius. He searched for an opening in the seam, and the thread snagged into it. He fused it into place, and felt the thread grow and wind on- touching many other lifelines, particularly those of the mutants. He could not fix everything. Tom Riddle's line could not be removed, and Harry's parents still died young. He would not live a perfect life, but he had never expected that. This was enough, it was more than enough, it was everything he could have dreamed of.
He took a mental step back, as if to admire his work. It was good.
That was when he felt another presence beside him. By necessity, a landscape formed around him. It was a place he remembered. It was the cold hauntingly beautiful mountaintop- the same one he had met Death the second time. It was night, the light of the stars barely illuminating the craggy landscape that stretched out in all directions.
"I hope you're proud of yourself." Death said.
"You know I am." He turned to face her. She was no longer a shadow, as they were not in the material world. She manifested in all her glory. That biting, bone deep cold washed over him, but it didn't overwhelm him. The unquenchable fire within him sent warmth out in plumes, it fortified him, and Harry found that he could face her. She looked as he'd remembered her, a picture of contrasts. Her deathly pale skin was clothed in a cloak as black as the night, with long jet-black hair and eyes that could swallow him whole.
"I'll admit it. I did not see Jean Grey passing the Phoenix Force along to you coming. That is what I get, I suppose, for entangling myself in the physical plane. I lost… perspective." Once, her very presence had been overwhelming, terrifying and yet horribly compelling. It was different now. He could still feel her, the vastness of her being, far, far beyond what any mortal could ever comprehend. He felt it like a massive boulder pressing against his chest. Yet the weight was easier to bear now. At least for the moment, he was not a mere mortal.
"Why are you here?" He asked, not quite able to look into the dark pits of her eyes.
"To make a deal." She said. Her voice was quiet, but it seemed to reverb in whispers that travelled through the wind.
Harry cast her a skeptical look. He well knew the unfortunate fates of people who made deals with Death. "I fixed everything, and I'm going to live my life now. What more can you offer me?"
"I can promise you and your loved ones full lives. You will all die peacefully in the fullness of time, when age takes you. That I can swear."
Harry's breath caught. "And what could you possibly want from me?"
"One night."
"What?"
She reached her hand out and cupped his cheek.The cold of her hand clashed with the billowing warmth of his body. His entire body was arrested by her touch, the mere contact was overwhelming, monopolizing his focus. "One. Night."
"Oh." He exhaled. "I'm flattered, but I'm not going to be unfaithful." He had slept with other women before, of course, but always with full discussion and consent from his partners beforehand. Despite his words, she drew closer, and he pulled back. His cheek tingled where her hand had just been.
"I'm not taking 'no' for an answer, Harry." Death said. "You've defied me twice before. You will give me this. If you resist me… you will find that I can be jealous. It'd be a shame if those women you care so deeply for were to… die prematurely. And don't you want your daughter to live a full life?"
Harry went cold, as cold as Death's touch. "You're threatening them." He said. "You're blackmailing me." He took another step back, and suddenly he felt her pressing in from behind him.
"One night is all I ask." She said. "I know you love offering yourself up as a sacrifice. Consider this another noble sacrifice." He was genuinely torn between protecting the women he loved and being faithful to them. It wasn't that they would treat this as a great betrayal, but they deserved his complete loyalty. With a burst of flame, he removed himself from her grip, appearing several feet away, but she was instantly there in front of him. He couldn't avoid her. He could either accept her deal or accept her consequences- except the consequences wouldn't be for him personally, it would be for the people he loved. He hated this, but he knew what he had to do. He would make it up to them, if they let him. He'd spend the rest of his life making it up to them.
"Why are you so obsessed with me?" He asked.
"You're the first mortal to ever best me." She replied, not denying his claim. Her dark hungry eyes raked over him. "You've refused and denied me at every turn. And I've seen you with those pathetic mortal women." She spat. "As if they deserve you, as if they could ever compare to me. Yet you deny me what you so freely give every mortal who spreads her legs for you." That was hardly true, he'd turned down many women- he wasn't that much of a slut. Still, she continued to rant. "You should be mine. But you've managed to slip through my fingers. So I'm going to take what I can."
Then she kissed him. With one hand she cradled his head, and with the other she pawed at his robes. They began to wither into dust that blew away in the wind. There was a crackling hiss as her mouth melted into his, like an ice cube being placed on a hot pan. He shuddered as her tongue invaded, plunging greedily into his mouth. She moaned loud and deeply, and it rattled him to his soul. When she pulled back Harry was left dizzy and shaking. She was so much.
The wind gusted, but he could barely feel the bitter alpine cold, even as it blew away the last of his clothes. He was fully exposed to her now, and Death could see the effect she'd had on him. She gazed at his hardened sex and licked her lips. Harry shivered, not from the cold, but of the memory of what that tongue could do to him. "You can't resist me." She said. "You're mortal, it's in your nature to reproduce yourself, to breed. You should be honored to give your life's seed to me." She let her midnight cloak drop, unveiling her body. She was pale, so pale that she nearly glowed in the night. She was also beautiful, hauntingly beautiful in a way he couldn't describe. She was slender, but her other features were lost on him, impossible for his mind to pin down. He couldn't look away; her body was impossibly compelling and it was having an effect on him. His cock throbbed into the icy air.
Harry gave in, officially and finally. He couldn't refuse her. "Okay." He said, his voice rough. "You win. One night."
Death fell upon him, her mouth feasting on his as she pushed him to the ground. He kissed her back, but she was restless and insatiable. She kissed his neck, her tongue carving along his jaw, pressing against his pulse and leaving a trail of saliva that hissed and evaporated in her wake. He let out a series of soft moans and felt her smirk against his skin. "See?" She crowed, finally lowering her body on top of his. There was a hiss as steam rose from where they touched, immediately condensing in the air. Harry moaned again as her body smothered his, her pristine skin against his marked flesh. "Its pointless to resist me." Her thigh slid against his cock, and Harry gasped. "Uhn, uh- god!"
Death's hand suddenly gripped his hair as she forced him to look into her eyes. He couldn't look away. They seemed to draw him in through sheer force of gravity. "You will call me Death or goddess if you must."
Harry nodded meekly, and Death rewarded him with another plundering kiss. He grasped at her, his hands finding no purchase against her impossibly smooth skin. He rocked his hips up into her. She pulled back. "That's right, submit to your base desires." She shifted her hips, sliding his shaft up to the apex of her thighs. "You will fulfill your biological imperative with me."
It finally clicked. "Wait." He rasped. "You mean, you- we- how is that even possible?"
She rocked against him, sliding his shaft along her perfect, lily-white lips. She was icy slick, but his heat began to thaw her until she was dripping. His body was primed for her and the sensation was far too intense to resist. He could feel her presence against him, vast ineffable against his mortal flesh. He came, screaming her name. He saw stars as he erupted, splattering his seed across her body- white on white. She threw her head back, letting back a moan. His seed froze to her, forming a glittering speckled trail along her chest and abdomen.
"I made this form for you." She admitted.
"Huh- ah- what?"
"I don't have a physical body or appearance." She said. "This is merely a representation of me, so that I may interact with you." He hadn't softened in the slightest, and she rubbed against his cockhead teasingly. "This is not about genetic compatibility. We will not have a biological child. This is… metaphor. You are giving me your life essence. I will use it. You do not even have to release inside of me, though..." She bore down on him, letting his cockhead slip inside. It was too much for him. He came again, unable to do anything except pump into her waiting emptiness.
"I need more." She moaned. Before he could even recover, she was descending along his shaft. She was doing more than just swallowing a part of his body, it felt like she was encompassing his life, mind, heart, and soul. He was descending into her. She was vast, an immense weight pressing in on him from all sides, on every point of his body inside and out, every shred of his psyche, and every facet of his soul. It felt like she was crowding him, struggling to bring every aspect of herself close to him. If not for the phoenix force, he would have been lost, but his internal flame kept him rooted. As everything around him became her, he remained himself.
She hilted him and moaned. He felt his very being vibrate with the noise. He was coming, pumping his essence into her waiting hunger like it was his only purpose, but the pleasure had become almost immaterial. He had never been more acutely aware of the fact that he was an ant next to her, and she a force of nature. He was absurdly lucky that a confluence of events had allowed him to defy her, and it was impossible for his victory to go to his head. Every gyration of her hips was like the rotation of planets, or the rise and fall of the tides, or perhaps more fitting for Death, a life cycle- the birth, life, and death of an entire generation in all its pain and beauty.
He could still see her on top of him, the pristine beauty of her form as she took him. He could feel the heat he was throwing off, and how it was thawing the ground beneath them- but it was all eclipsed. Her pace sped up, but Harry could feel how her presence swarmed in ever closer. He caught snatches of what she was thinking, aspects of her thoughts. From one angle he was blasted by her possessiveness, as intense as a hurricane in her conviction that he belonged to her. It was a feeling so powerful that it made Harry want to curl up and die. Then, from another angle, he sensed her picking apart every dream he'd ever had, almost all of them he'd forgotten as he'd woken up. It was not merely sexual, it was totaling. He could see how this could quickly become very horrible for him very quickly. How she'd physically, spiritually, and emotionally tear him apart to put him back together again. He was grateful that he'd avoided that fate.
He felt Death's ecstasy increase. She slammed her hips down on him, shaking with every pump of his release. "Yes, yes, yes! More!" She shouted. Her being closed around him unevenly, tightly in some places and loosely in others. It felt like she was trying to mold him, to shape his into something more fitting for her. He resisted her, but he didn't need to for long. She collapsed on him like a dying star, and exploded like a supernova.
The sun peaked over the horizon, and the once frozen landscape was now dotted with streams that were gathering into rivers. When Harry came to, Death was draped over him, her body cool and soft. She was panting, glowing with satisfaction. Droplets of water clung to her body like condensation on a glass. "That was." She said breathlessly. "Everything I hoped it would be."
"Good." Harry said weakly. He looked at the sunrise, the landscape was truly beautiful. Snowcapped mountains and clear rivers, under a pink-purple sky. "So, our deal is complete."
She went rigid. Casting a scornful look at the rising sun. "I… suppose."
"You aren't going to renege, are you?" He challenged.
"After that performance?" She scoffed. "No, you more than earned your keep. Unless you'd like another round?"
Harry shook his head. The experience had been… intense, but voluntarily sleeping with Death again, without coercion, was a line he'd never cross. He also worried about what she might do to him if he stayed with her for too long.
"Very well." Death sighed, wistful. She placed her hand on her abdomen. "I got what I needed."
"How is that going to work?" Harry asked. "What will our child… be like?"
"I don't know, not any more than any parent does." Death said. "Isn't that part of the fun?" He supposed it would be a novelty for her- a timeless, eternal being.
"Am I, going to get to see them?" He asked.
"If you want." She smiled. "I'll send the little demigod on down to you."
"And we're good, right? No more trying to kidnap me, messing with my life? Right? No more hopping universes, destruction or chaos."
"Harry, I promise I will not interfere with your life, or the lives of those you care about. But hopping universes? Avoiding chaos?" She chuckled, it was the warmest he'd ever seen her. "That's up to you."