Caroline is at the mall with her friends when a man attacks her with a knife. What she didn't know was that he was possessed by a demon- and that Heaven had sent three very beautiful boys to protect her.

You met Kim Joon-myeon in high school, and in opposition to your original belief that no man would ever fall in love with you and you’d be an old maid until death, you did indeed fall in love with each other. Through the ups-and downs of this relationship, what will happen? Will you live happily ever after in the end after all?