It's a summer battle between a volleyball team captain who doesn't want to wear a bra and a teacher who wants her to wear one (a "breast battle"). The volleyball team captain, who has had no sexual experience, is also resistant to bras and comes to school braless every day! Her homeroom teacher, unable to bear seeing her nipples peeking out from the gaps in her shirt, tries to warn her, but the volleyball team captain doesn't listen! "Why do you want to see my nipples?" "Does it excite you..."