Jeon Hyosung (19 years old)

Lee Kikwang (19 years old)

Lee Jinki (Onew) (20 Years old) 

Yoon Doojoon (21 years old) 

Lee Joon (22 years old)

Since childhood,Jeon Hyosung, Yoon Doojoon, and Onew live together in an orphanage called Home Sweet Home.
They grew up together and regard each other as family. As the oldest in the orphanage, three of them have to work to fulfill orphanage needs.
Doojoon and Onew is very protective of Hyosung.

Lee Kikwang is Lee Joon’s step brother.
Since his parents divorced, Kikwang was takencareby her mother who later married Joon’s father.