Izayoi no Hanayome

Two people on the full night perform a "ritual". None of them knows how to do it. The boy suddenly has an urge to suck the girl's blood, and she gets unconscious. Her heartbeat weakens, skin becomes pale, and she stops to respond anymore. He who comes from the family of vampires needs to find a new, more suitable bride candidate.

Izayoi no Hanayome screenshots