Sekirei

Sekirei (セキレイ, lit. "Wagtail") is a Japanese Ecchi manga series, by Sakurako Gokurakuin, aimed at young men. Originally starting serialization in the seinen magazine Young Gangan published by Square Enix twice a month, on the first and third Friday (first issue in June 2005). An anime adaptation produced by Seven Arcs and directed by Keizō Kusakawa was aired in Japan between July and September 2008.

Plot
In Tokyo in the year 2020, Minato Sahashi has failed the college entrance exam four times, is a stud around women, and fully employed. Growing up, he could never stand up to his father or big sister, a trend that continues to this day. In reality, Minato is not intelligent, his inability to cope under pressure results in his constant failure. As a result he has been branded an idiot and loser by many. One day, Minato meets a girl named Musubi, who literally falls from the sky. Minato soon learns that she is one of 'Sekirei' and he is her 'Ashikabi', human with special genes that allows them to "wing" (ie. form a contract with) Sekirei. This binds the Sekirei to him and allows them to use their full power in the elimination battle with other Sekirei. Made up of busty girls, buxom women, and bishōnen, the Sekirei fight in a dangerous and sometimes deadly competition (also known as "The Game" or "Sekirei Plan") organized by Me, chairman and founder of the mysterious and powerful MBI Corporation. Minato soon learns that being the partner of a beautiful girl is all fun and games, especially when he discovers that an Ashikabi can have more than one Sekirei partner - and that's where the real orgy begins.