One of the primary themes of the film is the exploration of first love and its complexities. Sung-min's innocent and pure love for Ji-yeon is contrasted with the harsh realities of the adult world. The film also delves into the social class differences between the characters, highlighting the struggles of those from lower-income backgrounds.

Beyond the age difference, the narrative emphasizes the "uneven" nature of their connection, as they belong to different social strata—a factor that further complicates their ability to find a lasting place in each other's lives.