After noticing the first years hanging around the pool, Run suggests a trip to the beach for summer vacation. Yūko and Nagi go swimsuit shopping, while Run gives Tooru her swimsuit from elementary school, do to Tooru's small stature. They soon arrive at the beach, where they have fun playing in the sea and sand.

Run ends up giving Tooru an undesirable haircut, but manages to fix it into something she appreciates. Tooru has trouble dealing with her erratic teachers while Yuko mistakes Yutaka's way of dusting out her neckerchief as a cry for help. When Yuko forgets a form she needs to fill in at school, the gang decide to sneak into the school at night to retrieve it, as well as do some exploring. As Nagi and Yuko go to the bathroom, they spot a strange glow outside, which they later discover to be Mr. Satō who then collapses, forcing the others to carry him to the nurse's office. At the end of the day, Yuko still forgets to collect her form.