In the second half of the summer break, the diving club have all taken an trip together to a popular seaside inn for a 3-day training camp. The group splits up into two bedrooms - the twins Ai and Makoto Ninomiya sharing a room, and the other room with Futaba Ooki, Hikari Kohinata, and Mato Katori, who has also brought the cats Cha and Ohime along.
Mato goes back to the car to fetch up her bags. While she's gone, the others check out their adjoining rooms until Futaba suddenly tells them to stop - she's spotted a cockroach climbing a wall. The girls all panic, then go to get Makoto, hoping he'll help since he's a "reliable male", but once he sees the cockroach he shuts himself in the bathroom and seals the bottom of the door with a newspaper. Next they lean out of the window to shout to Mato for help, but as soon as she hears there's a cockroach she gets into her car and drives away.
The girls continue to panic and try to find a solution. The decide that if they drown it in liquid detergent that might kill it, but when they check the washroom the only detergent is powder.
Ohime tries to catch the cockroach by climbing up the wall, so Cha tries to stop her but ends up running face-first into the wall instead.Hikari runs over and manages to stick the cockroach to the wall with some tape. Ai then pulls the tape off the wall and wraps it up in a ball, then stuffs the ball of tape with the cockroach inside it under the bathroom door where her brother is and blocks the door with a sweeping brush. He screams.