Yuka Uetsuki (voiced by Shiina Biru) is a professional skydiver. Her job is to ensure the personal safety of guests during skydiving. On the surface, Yuka looks fresh and sweet, but under such an appearance, there is a shocking secret. Yuka has the gene of a monster hidden in her body. Whenever she is emotional, this gene will cause Yuka to mutate into a terrifying cannibal. Yuka cannot control the actions of the cannibal, and many people have become victims of her. At work, Yuka met Toshihiko Momota (voiced by Kiuchi Hidenobu), who is honest and upright, and the two fell in love at first sight. However, Toshihiko also has his own secrets. He is actually a monster hunter who specializes in hunting cannibals. These two hostile people began a long and painful love journey. Momota Kazuma (voiced by Yoshino Hiroyuki) is Toshihiko's colleague. He has advanced ideas and strong action power. One day, Toshihiko and Kazuma's father were killed by monsters, and all the spearheads were pointed at Yuka. In order to survive and to clear their names, Yuka and Toshihiko embark on a journey of escape.