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Izuku is a bad person.
“Hush, little brother.”
Izuku is a very, very bad person.
“We don’t want to wake the others, now, do we?”
A tongue makes its way over the shell of his ear, dragging a gasp out of his throat, and Izuku tilts his head back in desperation. Scarred hands are at his throat, caressing just hard enough to remind him, just enough for Izuku to remember and lean into the touch like it’s everything he needs—
“Good boy.”
And it is.
He keens quietly as the villain pushes up inside him, the drag torturously, agonizingly slow. He stretches Izuku to infinity, tears him apart to the point he thinks he’ll die, and there’s nothing the boy can do but sit there and take it; nothing but sob brokenly against the chest of the person he wants and he doesn’t—
Shigaraki has his hips in a vice, and Izuku can tell that it’s him because of the way his hands grip him from behind. There’s a pressure to the hold of Shigaraki Tomura that’s unlike any other person, because it doesn’t feel like a person’s: it feels like a predator’s. A beast, digging its claws into the raw flesh of a prey. Teeth sink into the curve of his shoulder, and Izuku moans obscenely.
“My, my. Just as loud as you used to be.”
The voice that rasps against his ear is Shigaraki’s, but the words aren’t. They’re measured, curated in a way Shigaraki’s never are: a rational parasite taking over a creature of instinct. The voice makes him shiver, but the words make him sick.
“Hold still, little brother. Just a bit more.”
Izuku is a bad, bad person, because he’s a hypocrite on top of a traitor. Because the words little brother should make him sick, too, but they don’t. Instead, they make his skin grow warm and pliant, and he doesn’t have the strength to blame Yoichi for this; doesn’t have the guts to point fingers at anyone but himself.
Because, when All for One bottoms out inside him, Izuku begs him to keep going.
The pace is calculated; careful, at first. It has Izuku tipping his head all the way back and arching into it, voice breaking around tiny little whines that have the villain chuckling into his ear. “Filthy little hero. If your mentor could see you now.”
The words make him shudder, but before he can call out “Shigaraki—” the villain abruptly thrusts up inside him, forcing Izuku to throw a hand back and fist his hair for support as he bites his lip bloody to avoid crying out.
The pace is punishing. It tortures Izuku with every push, every stroke hitting him precisely where he’s most sensitive, where pleasure and pain blur together until he can no longer tell why he’s crying. Large hands rub gentle circles in his sides, and the tenderness of the gesture makes his skin crawl, but he doesn’t pull away.
Two fingers twist his chin back, and Izuku opens his eyes just in time to meet a blood-red gaze. Foreign, yet familiar. A stranger, and a piece of his soul.
The villain licks his tears away, and Izuku can’t tell which one of them this gesture belongs to.
“Beg, little hero. I’ll let you come if you ask nicely.”
And while he’s anything but a hero at this point—while the only reason the name doesn’t make him flinch is because Shigaraki calls him that; not little brother, not darling, not my heart—Izuku dives into the suggestion and hopes it’ll make him drown. “Touch me.”
“I said nicely.”
“Please…! Please, Shigaraki.”
Because, like it or not, this is the other half of his soul.
“Please, big brother, please—”
And the other half of his soul is split in two.
Rough, adoring lips crash against his, and Izuku lets them swallow him whole.