Kenko Zenrakei Suieibu Umisho

Kaname Okimura is a student of Prefectoral Umineko Shougyou High (Umisho for short) who joined the school's swimming club in order to learn how to swim, but the club is filled with weirdos, so he become a coach instead. Then, a happy lucky girl named Amuro Ninagawa who transfered from Okinawa appeared to join the club. Her underwater speed and swimming style surprised every club member, especially Okimura because she remind him of a mermaid like creature when he saw only once at childhood. The series created in 2007 and has 13 episodes. It is very funny but I recommended for teens and adults to watch.