Beasts are heteromorphic creatures, who are an enemy of mankind. Rei, nicknamed "Gehhyouki", is the strongest swordswoman, who has killed a number of those abominations.

Rei, along with her partner Arisa, are given charge to bodyguard Princess Aphrodia, who is studying abroad in Japan as their classmate. However, the Princess' birthday party is attacked by a terrorist organization composed of beasts and led by a mysterious figure. The invitees are taken hostage, and Rei and Arisa themselves are also captured.

Prepare for sex scenes with bugs, gangbangs, physical remodeling, forced pregnancy and etc. The minds of the girls are broken due to neverending cruel treatment by the terrorists. What is the real purpose of this endless erotic banquet?