Long ago, the gate to the world of darkness was sealed. Now evil warriors, known as Remnants, are trying to reopen the gate and let demons take over the world. However, at Tobira High School, there exist guardians of the gate who must risk their lives to prevent the gate from being opened.

In 2018 a young boy named 21 Emon dreams of becoming a space pilot and exploring space in general. He is the heir to a long line of hotel owners, which dates back to the founder of during the Tokugawa shogunate. Since the Earth has become a planet visited by tourists from all over the space, 21 Emon has to help out his family's business or they'll go bankrupt.

Hiroshi Ozora invents the Mol Unit, a device that makes its user invincible. His plans of becoming a super hero are short lived however when his sister, Mirai, accidently modifies the suit configuration. Now she is forced to save Tokyo by herself from the evil Machinegal and his gang of all-female androids. (Source: ANN)

Maze has gained incredible powers traveling through time and space, but she has also acquired one rather large problem: every night she turns into a really horny man. Unfortunately, Maze must rescue an equally lascivious princess from a mysterious warrior cult. Still, the male version of Maze would rather be chasing tail than rescuing willing princesses. (Source: ANN)