Kei has been a vegetarian and tended to have an unbalanced diet since childhood. He and his much older brother Sai, who has a brother complex but who's become reliable, get along well together.
For some reason, ever since he was a child, Kei has wanted to taste blood. Even though he knows it's wrong, he can't help thinking about it, so his university classmate, who cuts herself, agrees to share her blood with him. As soon as Kei discovers the taste of blood, he realizes he's always wanted to eat Sai…

Can Kei become aware of his affection for Sai without confronting his desire to eat him?