24 years old / 189cm. Black hair and grey eyes, the eldest brother. He didn't like Subin at first, but now he takes good care of her. He is a 3rd-year medical student and will become a real doctor in three years. He is blunt but cares for his siblings and treats them like a tsundere. (He occasionally looks after Seorin too.)

23 years old / 188cm. Black hair and black eyes, the second eldest. He used to grumble whenever he saw Subin, but now she has become an indispensable presence to him. He is in law school and plans to become a judge. He calls Suhyun 'Hyung' and calls the others by their names.

22 years old / 186cm. Navy hair and black eyes, the third brother. He used to say harsh things to Subin, but now he is the one who takes care of her the most. After graduating from the police academy, he is currently working at the Seoul Metropolitan Police Agency. He calls Suhyun and Sumin 'Hyung' and calls Subin and Seorin by their names.

21 years old / 168cm. Black hair and black eyes, the fourth child. She craves attention from her brothers and hates Subin. She is a sophomore at Korea University and is quite good at her studies. She is jealous of Subin, who always receives attention from their brothers. She calls Suhyun, Sumin, and Suhan 'Oppa' and calls Subin 'Hey,' 'You,' or 'Fake.'