In this adorable sister series episode 4, our protagonist becomes increasingly infatuated with his friend's little sister after spending every day at her house. He can't help but melt when she teasingly exposes her breasts or brushes against him. One day he decides to surprise her by bringing alcohol as a gift for her birthday party. As they both get drunk, he wonders if there might be something more than just friendship between them... But then she confesses that everyone else has boyfriends except for her, leaving her feeling lonely. Unable to resist any longer, he passionately kisses her and removes her pants before giving her an incredible handjob! However, things take an unexpected turn when they decide to have sex instead... Note: The contents may vary depending on the streaming method used.