First Time With Someone Older

University student Han San notices Ji Eun-Seong, who is working on a group assignment, and remembers seeing him having sex with a man in a bar bathroom the other day. San approaches Eun-Seong, who looks innocent, with a light heart... Why does it seem like he's just being swung around? It's all because it's his first time with someone older! (Source: Mr.Blue, translated)