Lunarken is a moth-themed Yin-Self Horror who is normally dormant until the night of a fullmoon where her bloodlust is at its zenith. Her host serves as a puppet body while her actual form is the orb hovering around it. Lunarken's body is portrayed by Emi Kitagawa (北川 絵美Kitagawa Emi)
Having possessed a woman who attempted to commit suicide over a man's insensitivity, Lunarken preyed on Hitoshi Morino, Hanezawa, and a high school girl when the three were in a stand off in a warehouse. Luckily, brought to the warehouse by a moth containing the host's final thoughts, Kouga Saezima knocks out the normal humans before killing Lunarken.