Ever since reading an article on a festival for the male genitalia, Mochizuki Yumeko can NOT stop thinking about the penis. It's not that she wants to have sex. She is just feeling this uncontrollable fascination with the penis. The only problem is that she has never seen a real penis. To satiate her obsession of witnessing a real penis, she looks into nude modeling. Now, she succeeded into convincing the timid, and only, member of her school's art club into nude modeling for her. Her journey into avant-garde male genitalia art beings.