Hikaru Tsutsui is a quiet, unassuming high school student who forsakes the company of his classmates to spend his time reading manga, playing video games, and watching anime. Hikaru is perfectly content to dwell in his 2D world, until one day he's assigned to clean the school pool with the beautiful Iroha Ikarashi, and she confesses her feelings to him. Will Iroha's affection draw Hikaru out of his shell? The movie is based on the manga of the same name by Nanami Mao, as well as the anime, which was adapted in 2018 and 2019.