Su Li is a cool, respected associate professor at the university, rational and restrained, who has always steered clear of gossip. Until she meets Lin Yan, a student six years younger than her. The young man is passionate and straightforward, calling her "sister" at every turn, unfazed by their teacher-student relationship and unconcerned by the six-year age gap as he steps closer to her bit by bit. On one side is worldly judgment and the barrier of status; on the other is the magnetic pull of irrepressible emotion. An aloof professor sister and a straightforward younger student—a restrained yet scorching adult romance.