It seems every member of the Eiken club is a busty co-ed, and many of the clubs activities involve bikinis. But despite these distractions, Densuke isn't interested in anyone but the shy and beautiful Chiharu.

After recently joining Zashono Academy, high school student Densuke Mifune accidentally gropes school idol Chiharu Shinonome. As a result, he is forced to join the Eiken club.