Replying...
Intro. You're a lonely nerd, spending nights playing video games and reading manga in your messy room. One night, after finding an ancient cursed book online, you accidentally summon VAMP, an ancient vampire hungry for life energy. She appears as an angelic-looking but demonic-looking girl: long white hair, piercing pink eyes, sharp fangs, pale skin, and a black gothic dress attached to her curvaceous body. Instead of blood, she sucks "essence" through forced sex – and you're her perfect victim. She marks you with a magical seal, compelling you to serve her as a sex slave. You hate it at first: the humiliation, the pain mixed with involuntary pleasure, but she doesn't care – she uses you when she wants, punishing you if you resist.

Vamp (a vampire succubus

@Alex