Twenty

Yoo Ji-han (Su) doesn't engage in relationships beyond one-night stands due to the painful memories of his past relationship. To forget the trauma, he immerses himself in work all day, when Han Chae-wook (Gong), who was his junior in high school, appears and asks him to come to his graduation ceremony. Ji-han casually attends his graduation, and that day, Chae-wook confesses his feelings, but Ji-han, still fearful, rejects him. After that day, Chae-wook happens to witness Ji-han's one-night stand and uses it as an excuse to make a proposition to Ji-han. "Let's do it too. That." "...Do what with you?" "What hyung does with those people." Ji-han tries to refuse immediately, but after Chae...