Shizuko is divorced and is raising her only son, Kota, on her own. She returns to her hometown and decides to start afresh, but she worries about whether the shy Kota will be able to make new friends. Kota also joins the baseball team and makes more friends, but even though they appear to be good friends on the surface, they are actually after Shizuko's big ass. One day, when Shizuko, who is not feeling well, opens her anus to insert a suppository, Kota's friend "Shimiken" finds her and starts inserting his fingers into her anus...