After slumbering for years in the darkest pits of the abyss, Haruki Shin is awoken by the demon lord of lust. She tries to remind him of a contract he signed with her in exchange for the power that would help him exact his revenge in the mortal world.
However, who or what he wanted to get revenge on? He couldn’t remember. Replaced with a hazy mist, his memories had long since faded. But to the mistress of lust that didn’t matter as she forced him back into the mortal world with the demonic body of an incubus.
Feeling lost he’s forced to adhere to each of her commands, and despite his refusal, he can’t resist the binds of the contract. Eventually, however, as he learns more about his tragic past, and the existence of the lustful system he’s been blessed with for his revenge, his path to becoming a monster finally begins.