Rebiya

A deal struck between a man named Duke Maerck and an ancient sex demon called Rebiya set a price in motion that has been feeding ever since. The OVA drops you into the present-day fallout of that pact, where Rebiya is still very much active, preying on the kind of emotions humans are most vulnerable to — hatred, the urge for revenge, and raw lust. The demon doesn't just show up and cause chaos; she works through people, pulling on threads of desire and resentment that were already there. That's what makes the setup interesting. It's less about a monster attacking and more about something ancient that understands human weakness better than humans do. The atmosphere is heavy and dark, leaning into the supernatural without much hand-holding about the mythology. If you've seen La Blue Girl or Demon Beast Invasion, you'll recognize the genre DNA here — Japanese folklore-adjacent demons tangled up with adult content. It's closer in tone to Bible Black if you want something with a bit more narrative weight behind it. At a single episode, it's a contained story rather than a sprawling series, so you're getting a focused slice of this world rather than a full arc. Don't go in expecting light viewing — the themes are deliberately uncomfortable, and that's kind of the point. If dark supernatural fiction with explicit content and a mythology-driven premise sounds like your thing, this scratches that itch.