Heito Tsukishina, who died after being forced into a murder-suicide by his yandere girlfriend, was reincarnated into another world.

"You are the chosen hero. Please defeat the wicked Demon Lord."

Granted ultimate cheat abilities by the goddess, he set off to defeat the Demon Lord.

One-shotting enemies, building a harem of beautiful women, and thoroughly indulging in his degenerate lifestyle.

(The Demon Lord will be a piece of cake anyway. Maybe I'll get a quickie in that forest over there before I go.)

However, he was unaware.

That his yandere girlfriend had also reincarnated into the same world and had already seized the Demon Lord's throne――.