[6][7][8] A slice-of-life story about five girls who live together in a sharehouse called "Belle Epoque" and how they connect over the growing pains in their youth.

[6][7] It was announced that Ryu Hwa-young would only make a cameo appearance, and that a new actress would be cast as the fifth girl of the Belle Epoque.

Park Hye-soo was also supposed to be part of the main cast, but due to a scheduling conflict, she stepped down from the role.

Unlike Ryu Hwa-young, this happened late into pre-production and it was decided that another actress would play her character Yoo Eun-jae; Ji Woo was cast.

[21] Onew was originally cast in the role of Kwon Ho-chang, but he stepped down in light of controversy surrounding him ten days before the drama's premiere, and was replaced with Lee Yoo-jin.