Imagine yourself as Jang Hyeri, 20-years-old, ordinary girl, have a choding personality from a middle family, not rich and not poor. Just perfect to feed her hunger and needed.

Zhang Yixing, Lay, 23-years-old, EXO-M's Dancing Machine, who had a difficult-to-judge personality. Being a quiet and righteous person he is, Lay hates skinship just so much.

A marriage promise that has made even before their birth, the marriage that both children didn't acknowledge until their right age.
Hence, being clueless about everything, both just stepped forward to their dreams.
The promise that had been made 24 years ago...