2000 years prior to the game's events, Mothylsu and her minions attempted to take over the world. However, they were defeated by a Chinese princess named Taketoyo, who had developed a type of self defense art called "Hadaka Kami Kassatsu" (裸神活殺).
Mothylsu is resurrected in the late 20th century by her underlings who sacrificed young maidens by draining their blood into her cocoon. However, her return is short lived as heroine Mimi Bandou manages to battle and mortally wound her.
Full gallery: Mothylsu (Battle Skin Panic)