Bom Yun is a shy and overworked high school ethics teacher who’s assigned to the most avoided class at Shinsu High School. The cause of its reputation is Jaegyu Seon, a confrontational guardian who terrifies the faculty. Yet as Bom gets to know him, she discovers a devoted uncle with an unexpectedly tender heart. Though Bom tries to keep her distance when Jaegyu openly pursues her, she soon finds herself hopelessly falling for this quirky but charming giant of a man.