Anime Crossover: Obsession Becomes Reality, and a Yandere Girl Comes After Me

Modern anime crossover / everyone turns evil / inner demons made manifest / mild supernatural elements / mostly obsessive, possessive love

Series included: Oregairu, Angel, Mieruko-chan, Bocchi the Rock! (early on)??, (Girl Monsters), With or Without Spikes, MyGO!!!!!, The Girl Next Door, Komi Can't Communicate, Macross, Dress-Up, The Quintessential Quintuplets, and more.

After transmigrating to a crossover world overrun by vengeful spirits, Hoshimi Yuu survives by relying on the “Hyper Zetton” inside his ring.

To raise this ultimate weapon of the universe, he moves among all kinds of beautiful girls, coldly withdrawing just when they're happiest and harvesting the vast despair and other emotions they leave behind.

Once his power is complete, he promptly disappears and becomes a model student at a new school.

But peace doesn't last long. A gigantic claw mark appears in the sky, and the vengeful spirits begin breaking through their boundaries.

During the retreat, Kato Megumi, hidden in the shadows, taps his shoulder with an eerie smile.

“Yuu-kun, I've missed you so much. I want to devour every last bit of you.”

Terrified, Hoshimi Yuu jumps back, only to fall into a soft, warm embrace.

He looks up to see Nijika Ijichi, the angel herself, surrounded by thick black smoke. She smiles gently.

“Don't be scared. We won't hurt you. We just want you to be a little more obedient, so you can never leave us again.”

Looking at his ex-girlfriends, all of them completely corrupted, Hoshimi Yuu panics at first. Then he remembers the thing inside his ring and straightens up at once.

Before he can even get to his feet, countless pairs of scarlet eyes light up in the darkness, and the composure on his face freezes completely.

Deep within the black haze, a pair of cold hands gently wrap around his neck.

A voice that absolutely should not be here rings out with a soft laugh:

“Yuu-kun, did you really think... you were the one using us?”