Crush and Blush

Crush and Blush Hangul RRMisseu Hongdangmu lit. Miss Hongdangmu or Miss Carrot is a 2008 South Korean film. It is the feature film debut of director Lee Kyoungmi, and also the first film to be produced by Park Chanwook.

Yang Misook is an unpopular and frumpy high school Russian teacher, who has a habit of going red in the face. For ten years she has been harbouring a crush on Seo Jongcheol, her former teacher and now married colleague, though he is more interested in pretty new teacher Lee Yoori. Misook tries to put a halt to this blossoming romance, forming an unlikely alliance with Jongcheols daughter, Jonghee.

Source: Wikipedia