Synopsis: 100-il Sarang

Ria becomes angel number 5623 after a fatal accident. Despite being in the afterlife, she cannot let go of memories of her former boyfriend Ban Ji Hwan. When Ria discovers Ji Hwan's name in a book predicting people's deaths, she begs the angels for help. Ria takes over the body of a shy girl named Hae So who leads a boring life, unlike Ria's outgoing personality. Despite facing bullying from Hae So's half-siblings and mother, Ria remains determined to reconnect with Ji Hwan. However, when she eventually finds him, Ji Hwan fails to recognize her.