AN: Like all my works, this is cross-posted from AO3.
Pyrrhic Victory
Yoru scowled, chest heaving and heart pounding. Chainsaw Man approached, his figure a black shadow towering over her, the sound of the chainsaws on his face and in his four arms whirring in her ears.
Every part of her ached with each wretched breath of icy air. Covered in gashes as she was, she was losing far too much blood; even with her presence, this feeble human body healed all too slowly. Falling Devil's devastation had led to many countries going to war, but even the power that fear brought her wasn't enough to combat the Chainsaw Devil. She should have killed him a dozen times over—indeed, she'd left him lying on his back that many times—but a dozen times his motor revved and he stood back up.
And in all those beatings, not once did he have the decency to give back her nuclear weapons, or the chunk of her body he'd bitten off. No, the only one coughing up anything was her, droplets of blood staining her shirt every time she did. To Hell with revenge; at this point she just wanted her damned nukes and power back. Or to escape with her life.
The ground beneath her quaked as he took a slow step forward.
He knew he didn't have to move quickly; it's not as if she could run. That, and he was soft—reluctant to kill the human his own human had fallen in love with.
So much for the weapon they'd created from Crambon's bones, dug out of his grave; Asa's guilt at using her cat's dead body had been so intense—coupled with the residual guilt Yoru may have felt for putting Asa through defiling her pet's grave—Yoru was certain it could kill Chainsaw Man… He was injured, but Yoru had expected death.
In hindsight, she'd failed to defeat him last time, even with the help of her sisters, and the weapon devils. What hope did she have this time? Here, in a weakened body, with nothing but…
A dizzying chill coursed through her spine, and her hairs stood on end…but not because she saw her impending death. It was the opposite: she saw a way out; a way to escape death; one last tool she had at her disposal.
Another clambering step forward, and a cloud of dust at his feet where those buzzing blades shredded the ground. Not all that differently to how they would shred her flesh.
Her consciousness detached from her body, allowing her to watch her last 'tool' take shallow breaths. Asa.
Yoru was the War Devil, and war meant forging plans for any contingency; it meant making sacrifices in an emergency. In the beginning, Asa would have been little different to any other human weapon—pathetic, because what devil felt guilt over a human? What weakling of a devil cared about anyone but themselves?
But after months having shared a body?
Shared a brain, with all the feelings spilling over from the connection?
Shared love?…
Even as she knelt down and put her hand on Asa's head—ran fingers through her grimy, dusty, messy hair, and along her soft cheek—Yoru wavered.
She could do it; with but a few words she could have everything she wanted. She could defeat Chainsaw Man, bring back nuclear weapons, and regain her full power as the War Devil; humanity would fear her name forever.
But to win the battle, she'd have to sacrifice someone she cared about.
Yoru swallowed; the uncertainty hurt; her throat ached, feeling sticky and raw, like the skin had been ground away. Her fingers shook against Asa's warm face, and Yoru fought to hold her breath steady.
Hurry. Decide.
It sounded so easy, back when she formed the plan to weaponize her host's life and take the body for herself. A simple, dispassionate scheme, with an input and output. Ore melted and shaped into a sword. A tree to be cut down to make a spear. A mere arrow, to be left stuck in an enemy's corpse after being used.
Yes, she knew it would require guilt…but she'd never really known what that meant until now. It meant a sinking pit in her chest. She never thought the ore would be so pretty; never thought she would feel bad for hurting the tree; never thought the arrow would have to be plucked out of her own heart.
Her heart thumped in time with the enemy's heavy footsteps.
He was nearly here; she had to do it, now.
But then…this was Asa. The girl who sympathized with her fear of being forgotten and erased, unlike other devils who would try to abuse her weakness. The girl who saved her life—admittedly in return for saving her own, but still. The girl who comforted her when she awoke from nightmares about being eaten by Chainsaw Man.
Despite the injuries and rattling breaths, Asa looked peaceful now; the expression not unlike the one she had while sleeping in Yoru's arms…
Yoru jerked in place, and twisted her head around at the deafening buzz of chainsaws revving up.
Her breath halted and her heart pounded as she stared at the devil, standing closer than she thought—in near striking distance.
She stared, quaking at those infernal, bloodstained saws spinning; those gleaming, pointed teeth, forming the gates to the void in his stomach, where she would rot and be forgotten!
No! This couldn't be it!
Without even turning from the chainsaw-brandishing devil, she gripped Asa's hair and yelled with what little breath she had, "Asa brain sword!"
A surge of life flowed into her, along with a surge of something sickening, like rotten meat. She felt her illusory form merge into Asa's solid one, while the skull twisted and cracked under her own fingers, making a grotesque crunching sound.
How laughable; the mighty War Devil, squeamish over the sound of a head cracking open.
Asa's—no, now Yoru's—skull reformed, and the jelly-like brain matter in her fist solidified, into a warm fleshy handle as Chainsaw Man lunged at her.
Her body acted alone on raw, unthinking instinct; she rolled to the side to dodge the slashing blades, but she fully expected that the Hero of Hell would follow up with another strike—raising her new weapon to defend against it, and sure enough, a whirring blade struck with a screeching clash; hundreds of sparks flew off the contact point where his saws tried to slide through, bright enough to blind a human from this close.
Her heart thudded and pulsed, pumping fire in her veins; for the first time, she saw the sword's full glory with her own eyes—grey, with coiling, thick wrinkles and folds, like scrunched up paper, or the roots of a tree. Once made of soft fat, now encased in a glasslike, sharp sheen. It held an edge that seemed to sink into Chainsaw Man's own four blades, rather than being dulled or cut. Across the veinlike patterns within, an electric glow swam across, with all the speed and chaotic branching of lightning.
That used to be her. That flesh, this flowing electricity…
Chainsaw gave Yoru no time to think, only to feel the trails of wet down her cheeks.
She ducked and dodged on autopilot; where before each blocked strike would shatter or dig into her weapons, now his were breaking—jagged teeth of his chains snapping off.
His near invincible black armor was cut away, piece by piece, and he yelped when Asa stuck in his arms and the electricity shocked him.
He tried biting it, but he instead broke his teeth, and earned a slice in his jaw.
It was working; she ought to be delighted. He was being worn down, while Yoru, on her end, never felt more full of energy and inexhaustible vigor…
Never felt any emptier inside her gut, either. That curdling, sick unease would fade, right?
It had to fade.
Every swing filled her with adrenaline, and made her tremble; her aim grew sloppier, but it didn't matter, because he was crumbling, lurching, coughing up blood.
She'd learned humility from the last time they fought, and from living with Asa, but this time it was no arrogance: Yoru already knew she'd won.
Their first two long battles had left her beaten, and now in mere minutes, the power of her sword had left him on his knees—panting, bleeding, every chainsaw broken and shattered.
She was panting too, but certainly less bloody. Actually, she was soaked in it, but it was all his.
A smile-less laugh crawled up from somewhere inside her, as she pointed her blade at his face. The sharp point quaked, as her arm muscles were taut but wobbling. "I win, Chainsaw Man."
She was surprised with how weak her voice sounded; if she could have convinced herself it was just tiredness, she would…but the stinging in her eyes refused to let her deny the true reason.
He didn't respond. Actually, he made a gurgling, buzzing sound, but it didn't sound like any words she could understand. Why did she feel disappointed? What was she expecting? An admission of her superiority? Awful, unbearable judgment for how she'd attained victory? Why did she care what her sworn enemy—the devil who had devoured most of herself, and her greatest allies—had to say?
She skewered his chest, cutting through his ripcord in the process. She watched with dead eyes as his filthy blood defile her blade, and the his body tense and smoke as the electricity surged into him. This should have been the greatest moment of her life; it should have been a triumph.
His imposing presence left, and what was remained was a corpse full of corpses.
With the bodies of those ancient devils freed from her enemy's belly, new memories entered her mind—or rather, old memories, of a second World War, atomic bombs, power, completeness. This was the victory she'd wanted, and earned!
Yoru fell to her knees, scraping them on the stone; they healed in no time at all.
I didn't even say goodbye. I didn't tell her I was sorry. She didn't even know I would…
It turned out the chainsaws and teeth weren't to blame for her ragged breath, or the waves of frost crawling across her skin. Now the fog of war had cleared, and she could think again, she couldn't pull the sword out and admire the weapon that slew her enemy; looking at it made her jaw quiver.
She blinked silent tears out of her eyes—once Asa's deep brown ones, which Yoru had grown quite used to staring into from between Asa's legs.
Hair raised on her neck—the neck Yoru had kissed, pulling so many sweet moans and whines out of.
Her body trembled—the body Yoru had held and stroked soothing circles into when Asa woke up from the nightmares about losing her mother. 'I just want you to calm down so I can get some sleep', she had lied, but Asa clearly knew; she said the same thing in return when it came to Yoru's bad dreams.
She would give anything to feel that warmth at this moment; to hear those stupid fucking thoughts about poetry and sad music; the thoughts about other girls and guys which filled Yoru with jealousy; to feel those social anxieties and worries and self-doubts leak from Asa's mind into hers, as loathsomely human as they were. Because that would mean she was there.
Why did that stupid dog have to push Yoru this far? Why couldn't he have just lain down and died?! At this very moment he had probably been reborn somewhere on Earth, but humans only lived once.
Oh it would have been so much easier if she could actually convince herself to lay all the blame on him right now.
Yoru put a hand on the brainlike sword's hilt. She took one last tearful look at the weapon that had been her love—the one who was now dead, because of her selfishness—and her head fell to face the bloodstained dirt, heavy with guilt. Her lip wavered, before she broke out into miserable sobs.
She was so pathetic; sacrificing a mere human should mean nothing to a devil like her; wretched weeping like this was hardly befitting of War.
She didn't care; Asa wasn't hers anymore, and would never be hers again.