As the child of a human and a succubus, Miori spends her days at a church she ran off to as a child, trying to keep her hunger under control. However, as a man's life force is essential for her survival, she regularly sucks small amounts from her childhood friend Mahiro... Until one day, their relationship slowly begins to change.

Miori una niña mitad humana mitad sucubo huye de su casa cuando su padre intento matarla al enterarse que la madre de Miori lo abandono, luego de escapar llega a una iglesia, Miori dada su condición de sucubo debe de tomar sangre humana, en ese momento es cuando entra Mahiro un chico que creció junto a ella en la iglesia.