is a Japanese manga series written by Yamato Koganemaru (first 31 chapters) and Hiroyuki Yatsu (onwards) and illustrated by Namoshiro Tanahashi.

In High School, was serialized in the same magazine from May to November 2010, with its chapters collected in three volumes.

[3] Kodansha collected its chapters in 11 tankōbon volumes, released from February 16, 2007,[4] to January 16, 2009.

In High School, was serialized in the same magazine from May 26 to November 2, 2010;[6][7] a three-chapter extra story, titled Hammer Session!

[22][23] The series stars Mokomichi Hayami as Goro Hachisuka and Mirai Shida as Kaede Tachibana.