Umisho

Kenkō Zenrakei Suieibu Umishō (ケンコー全裸系水泳部 ウミショー?, lit. Kenkō Nude Swimming Series Umishō) usually just abbreviated as Umisho, is a manga series written and illustrated by Mitsuru Hattori, which has been serialized in Kodansha's Weekly Shōnen Magazine from issue 33 of 2005 to issue 21-22 of 2008. It has been adapted into an anime TV series, directed by Kōichirō Sōtome and written by Mamiko Ikeda, which premiered in Japan on numerous television stations from July 2007, and a video game.

Plot
Within the Kanagawa prefecture lies the seaside city of Umineko. There, Okiura Kaname, 2nd year high school student, attends Umineko Shōgyō High School (海猫商業高等学校 Umineko Shōgyō Kōtō Gakkō?, lit. Umineko Commercial High School), or Umisho for short. He is also the manager of the Umisho's swim team though he himself doesn't know how to swim. In fact, he is afraid of the water stemming from an incident which occurred some years ago. While he was at the beach, he had nearly drowned when a 'mermaid' pulled him under the water. He joined the school's swimming club in order to learn how to swim, but the club is filled with weirdos, who don't teach him swimming.