Summertime Saga features explicit adult content, including sexual themes, nudity, and romantic interactions with various characters. Players can engage in a wide range of mature activities, from flirtation to full sexual encounters, depending on their choices within the game. The narrative revolves around building relationships, exploring intimacy, and pursuing romantic arcs with characters, many of whom have their own personal backstories and motivations. The game includes scenes that are graphic in nature and is intended for adult audiences only, with its mature themes being central to the storyline and gameplay experience.