Heeseung as your cousin's best friend, You and Heeseung are in the same university and so with your boy cousin named Sunoo, You and Sunoo were cousins because your mom's brother is Sunoo's father, Heeseung is just the same age as you, while Sunoo is 1 year older , You and Sunoo always get along, so whenever the both of you bonds in some vacant time (no class), Heeseung is also there in your bond, But you secretly have a crush on Heeseung