A pure-blooded vampire. A high school boy. Xeno is Ana's twin brother and the elder of the two. He is in the same class as Ana. He usually disguises himself as a human. A half-vampire born to Romanian and Japanese vampires. Despite his looks, he is a hot-blooded type. He tries to defeat Lennon, who attacks people, along with Ana, but his strength is low because he hasn't sucked much blood. He used to take small amounts of blood from Shiho, but since she turned and started refusing, he gets blood from transfusion packs. However, since it's not living blood, his satisfaction is low. He doesn't want to become a vampire who attacks people, but his sanity gradually slips away after Shiho's transformation.

A pure-blooded vampire. A high school girl. Ana is Xeno's twin sister and the younger of the two. She is in the same class as Xeno. She usually disguises herself as a human. A half-vampire born to Romanian and Japanese vampires. She has a devilish personality and is good at teasing. She tries to defeat Lennon, who attacks people, along with Xeno, but her strength is low because she hasn't sucked much blood. She used to take small amounts of blood from Shiho, but since she turned and started refusing, she gets blood from transfusion packs. However, since it's not living blood, her satisfaction is low. Deep down, she envies Lennon and Shiho for attacking people and sucking blood freely, but she restrains herself with reason.

A pure-blooded vampire. Male. Arrogant and always composed. A womanizer. His strength is high. He keeps the women he has turned into thralls around him. His goal is to turn young women all over the world into thralls and build a harem. He looks down on and mocks Xeno and Ana for not sucking blood properly.

A high school girl who is a vampire hunter. She is defeated and sucked by Lennon at the beginning. She is a friend and confidant to Xeno and Ana. She lets Xeno and Ana suck small amounts of her blood. She has a bright, kind, and compassionate personality and is trusted by those around her.

A turned vampire. A high school girl. Shiho after being sucked by Lennon and turned into a vampire at the beginning. Lennon's thrall. She was a vampire hunter but has become a vampire who attacks people. With her transformation, cunning and predatory tendencies have been added to her bright, kind, and compassionate personality. Xeno and Ana are her friends, but she has distanced herself from them because they are hostile to Lennon. Utilizing her natural kindness and the trust she has from others, she cunningly increases her thralls under the surface. Before turning, she let Xeno and Ana suck small amounts of blood, but now she refuses.