Kim Yongsun is a special girl. Ever since she was little, she has unbeatable luck. All the girls in her class even come to her to ask for luck with the boys they like! Although an orphan, Yongsun is not sad. She still has her older sister, and together they fight through everything. But one day, Yongsun meets this strange attractive girl who demands that she gives the only memento she has of her mother to her…