Series · Shōnen Gahōsha Hey! Riki (2004) Hiroshi Takahashi, Koichi Nagata 30 issues Issues #1 · Vol. 1 Jul 9, 2004 #2 · Vol. 2 Sep 30, 2004 #3 · Vol. 3 Jan 26, 2005 #4 · Vol. 4 Jul 11, 2005 #5 · Vol. 5 Nov 10, 2005
