Moving in with his Aunt Meme in the city, Makoto Niwa never expected to be rooming with a futon with legs. Turns out, this mysterious creature is merely his cousin Erio, a self-proclaimed alien. Having disappeared for 6 months with no recollection of the event, the entity known, as Erio just keeps getting more bizarre. So is cousin Erio just a ruse? Is she really from outer space? And what exactly happened in those 6 months that she had disappeared. Makoto may not have the answers at the moment but he knows one thing for sure, he needs to bring it all back down to Earth.