Part 1 - Hara Sayuri is a student who lives alone in a cheap apartment. In order to earn money to pay the rent, she holds a number of part-time jobs. Today, she is washing the upper windows of a building. Coincidentally, she finds herself cleaning the windows of the office in which her elder brother is working. However, when she calls out to him, she sees him get an erection! Seeing that, Sayuri removes her clothes and proceeds to strike provocative poses… Part 2 - Kagurazaka Fumina is a cosplay-lover and works part-time for a maid service. Today, she has been working since morning for her new master. Cooking, laundry, and cleaning. While tidying up, she is suddenly assaulted from behind by the master! Although she tries to resist, she gets turned on when he massages her big breasts. Finally, from behind… Part 3 - Since graduating from university, Oshikiri Momoka has been working as a home tutor. One day, she falls asleep while tutoring a cute boy. Seeing her like that arouses his sexual desires. When Momoka realises, she slowly removes her clothing, and the lesson on becoming an adult begins!