In Japan four Zaibatsu Conglomerates sponsor underground death matches between genetically engineered hybrids called Therianthropes who combine the intelligence of humans with the power of animals. A high school girl named Hitomi Uzaki is kidnapped by several men intending to rape her with college student Yūya Nomoto forced to drive the van. Before he can save her, Yūya finds that Hitomi has easily killed her attackers and is forced to drive to an arena for a fight between herself and a lion hybrid. Hitomi wagers that she will win, betting the money that Yūya's organs would fetch if harvested and sold. Hitomi reveals she is a hybrid of a honey badger, the most fearless animal in the world, and easily kills her opponent. Yūya is informed by Hitomi's guardian, Reiichi Shidō, that the Zaibatsu use death matches to attract wealthy investors and gain political and economic influence. Due to Hitomi betting his organs, Yūya is technically the only investor she has allowing her to take part in matches. Hitomi is ordered to protect Yūya, who is given Hitomi’s prize money, 100 million, to bet on future fights. Later, Yuuya is attacked by another Hybrid wanting to learn about Hitomi.