High school student Takeru Takemoto works part time as a (motor)bike courier. During one of his deliveries, he saw a mysterious light passing him and fell into a forest. What he had found was a beautiful girl coming out from a glowing cocoon, calling herself “Hikari.” While Takeru was quite embarrassed because of Hikari's nudity, a strange monster suddenly showed up and immediately attacked the two. Both Takeru and Hikari demonstrated the power of their other selves before Takeru had a clue of what's going on. Ryou and Takeru are typical high school students. That is, until Takeru finds an alien calling herself Hikari. Takeru's life is suddenly filled with aliens and monsters and a drunken robot and he's just trying to keep everyone safe while he figures out what the hell is going on. Takeru is a typical high school student until he saves Hikari, an alien girl with no memory of her past. Committing himself to take care of her, Takeru's life is suddenly filled with aliens and monsters.