Yuka Sawamura, an investigator who protects the peace of the city, encounters a scene where civilians are being attacked by demons. Yuka pretends to go to call for help and transforms into "Beauty Mask Fontaine". Fontaine defeats the demons and helps the civilians, but is attacked and defeated by the demons that are hiding and lurking. Fontaine, who was trapped in the hideout of the demon tribe, is sexually violently blamed by the executives. Fontaine, whose reason has collapsed due to the devilish deeds of the demon tribe, is imbued with despair and hatred, and transforms into a warrior "Dirty Fontaine" who is loyal to his own desires. Dirtyfontaine, who purifies the demon tribe and returns it to its original human state, and makes the human a prey to his own carnal desires, smiles lewdly and wickedly. ［BAD END］