The story revolves around a highschool boy named Niwa Makoto. He lives with his aunt&rsquo;s family since his parents are away on business. It is there where he meets his mysterious cousin of the same age Touwa Erio &mdash; who happens to tie a futon mattress around her upper body and is a self-proclaimed alien. Her staple food is pizza. Erio had been missing for half a year and was found floating in the sea. She doesn't remember anything about what happened during that period of time, but she began to think that it was the act of an alien and wanders the neighbourhood wrapped in the futon.

The story revolves around a highschool boy named Niwa Makoto. He lives with his aunt&rsquo;s family since his parents are away on business. It is there where he meets his mysterious cousin of the same age Touwa Erio &mdash; who happens to tie a futon mattress around her upper body and is a self-proclaimed alien. Her staple food is pizza. Erio had been missing for half a year and was found floating in the sea. She doesn't remember anything about what happened during that period of time, but she began to think that it was the act of an alien and wanders the neighbourhood wrapped in the futon. 
(Source: AniDB) Note: This includes the extra novel Denpa Onna to Seishun Otoko SF (Sukoshi Fushigi) Han

Makoto Niwa just moved to the city to live with his aunt Meme after his parents were reassigned to work overseas. He is perfectly fine with that, saying it will give him the chance to live the dream life of an adolescent boy. He keeps track of the things he does by assigning "points" to them—positive or negative—and adds them up on a regular basis to grade his adolescent life. 
 
And then he discovers Meme has a secret daughter (and self-proclaimed alien) named Erio. He finds her rolling around by the front door of Meme's house wrapped up in a futon. It is then he realizes that his dream adolescent life will not come true, and begins a life of experiences that are out of this world. 
(Source: NIS America)

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