For her disabled father and to protect her family which is on the verge of breaking up, high school teen Cheong-ah maintains life by working at a gas station. The owner of the gas station Dong-pal pretends to comfort her, but in the end his desires overwhelm him and uses money to take away her virginity. Dong-pal starts obssessing with her in the name of love and from then onwards, Cheong-ah abandons herself and throws her physical self out there. Then one day, San-hae, the owner of a medium-sized business who parted with his family and lived a lonely life, sees Cheong-ah sitting under a lamp post with a blue rose in her hands. A strange emotion sweeps over him...

Every few hundred years, the most powerful demon on earth—a snake demon—awakens, and the Yin-Yang Masters are summoned to the capital. Meanwhile, the Princess of the realm has her own plans, as she conspires to claim the demon’s power.