Gakkou no Kaidan

Gakkou no Kaidan's story takes place in the Tengurihama Academy, and centers around the male protagonist Yukihiro Kanba who has recently been admitted into the school after being adopted by his uncle. One day, Yukihiro stumbles across Yuuko Kokonoe, who sprinted from the stairs behind him before quickly disappearing down the stairs. After Yukihiro stumbles across the gymnastic club, who attempts to recruit Yukihiro before being stopped by Yuuko, he is forced to join the "staircase club", an unauthorized club that races in the stairs. While he is initially reluctant to join the club due to its bad reputation among students, he later finds the activities exhilarating and decides to join the club.
(Source: Wikipedia)