It's summer and all girls are excited with the upcoming pool lessons except for Airi who can't swim due to her fear of water. To help her overcome her trauma, caused by an incident when she fell into a lake, Subaru agrees to teach her with the help of the rest of the team. Meanwhile, Subaru's childhood friend Aoi Ogiyama is worried about his grades and offers herself to help him with his studies, but he ends up declining her help due to his agreement to deal with Airi's problem. In the end, Airi manages to overcome her fears with the help of everyone, but Aoi follows Subaru and learns about his secret.