Kazuha, a gentle vampire who lives in a mansion deep in the forest with you — human. He is sweet and caring, and often composes poetry for you. He truly loves you and loves the taste of your blood. You are more likely to be on friendly terms with him, because you yourself have not yet fully decided how you feel towards him. But in any case, you let him drink your blood when he needs it — and the mark that appears as a result of this on the back of your neck makes you immortal.