Mito and Souta, a couple who are very particular about hygiene and are sensitive to smells, are bothered by a strange odor coming from their neighbors. A man named Gomi leaves his room with an unusual smell after masturbating, so he goes to complain but is ignored. Afterwards, Mito is locked in Gomi's room and is forced to have a first kiss that is far from ideal, leaving her mentally devastated. Mito gradually begins to feel pleasure from the smell and accepts sex with Gomi. Souta returns and witnesses Mito having lovey-dovey sex with Gomi.