Vampire rules

The Earth has been destroyed and ruled by the vampires. A high school girl named Aoi Tsukino is seeking revenge for her family that became a vampire and died after she met a handsome guy named Zen Maki and they became friends. Zen Maki has 3 brothers and he is the 2nd younger brother among of them. Zen Maki is the son of the vampire king and Zen lied to Aoi about his true Identity because he wants to protect her.What will happen if the vampires discovered that Zen has a human friend?