On Christmas Eve, the female lead makes a wish and, due to a slip of the hand, writes Santa Claus as Satan, accidentally summoning the handsome and arrogant demon 937. He acts disdainful on the outside while doting on the female lead. The female lead carries a huge sum of money back to the orphanage to repay her gratitude, and later passes away from terminal stomach cancer. For the first time, 937 experiences heartbreak and crashes heaven to confirm his feelings. The female lead is reincarnated with amnesia, only sensing that she is being watched by a strange presence, and 937 is also disciplined because of her causing chaos.