Nam Woo-joon is just an average junior player— quiet, unremarkable, and always standing in the shadow of his idol: Seo Si-won, a badminton genius and national representative. Woo-joon has always admired Si-won from afar, never thinking of him romantically. But one night changes everything. After waking up to find Si-won doing something unthinkable while he's asleep, Woo-joon's simple world is turned upside down. What begins as confusion and betrayal slowly unfolds into something deeper, as layers of longing, misunderstanding, and emotional tension rise to the surface. Can someone so ordinary survive the intense smash of love from a genius who doesn't play fair— even off the court?