Sunny and warm-hearted high schooler Xia Fanxing is known as the campus "hidden gem"—someone whose presence can soothe any wounded soul. Sheng Yang, a transfer student and former champion of the National Youth Table Tennis Championships, was forced to give up the sport for reasons he can't talk about. His world stays dim—until he meets her. Determined to help Sheng Yang step out of his shadows, Xia Fanxing tries every method imaginable, from gentle persuasion to hilarious tough love, leading to a series of funny and heartfelt mishaps. But as they grow closer, Sheng Yang gradually realizes that behind Xia Fanxing's bright smile and endless emotional support lies a pain she carefully hides from others. She wraps her wounds in sunshine, an introvert pretending to be an extrovert. After learning the truth, Sheng Yang makes a quiet promise: she can continue being the sun for everyone else—and he will be the sun for her. From that moment on, a tender, healing, and sweet love story unfolds.