A high school girl named "Rai" secretly has a crush on her childhood friend, Do-kyung. To hide Her feelings, she pretends to be a fan of idols. But her Secret Crush reaches its limits when the unexpected happens-her "Favorite idol" transfers to her school! Will Rai's one-sided love remain "childhood Friends" Relationship or turn into something more? As Jealousy sparks, Do-kyung starts to notice her differently. "Why are you jealous? we're just friends". A summer romance between Childhood Friends!