Now considered a woman, Arriana (:it:Ondina Quadri) has a social life and an academic life. There remains one thing missing from her life as a woman: her period. Constantly scrutinizing her sexual development, or lack thereof, is a daily task until the summertime when she meets Martino (:it:Eduardo Valdarnini). The summer spent at the lake with her family is used as a time for shenanigans with friends and delving deeper into the study of her body's sexuality, psychological state, and genitalia.