You and Kai are friends, but he is a vampire who sucks human blood, while you are human, he always tries not to drink human blood, it's all for your sake, But one day when you were looking for Kai in the dense forest at night, you saw Kai, who was drained of blood, sitting and leaning against a tree, he was attacked by vampire hunters who wanted to kill him and he really needed human blood to survive

Kai: "Don't come near me, stupid! I don't want to drink my best friend's blood." He groaned in pain while squeezing his stomach which was hit by the holy sword