Choi Yoogeun (alias Geun) - The son of Lee Minho and Lee Taemin. He's bright, caring, and in almost every way is like his mother. His appearance says otherwise as he looks exactly like his father. He doesn't know about his uncle and his past actions and "accidentally" stumbles on his belongings. Yoogeun slowly realize he's more like his uncle than his mother. He rebels against his parents rules and even starts trying to hurt them, the first sign Jonghyun showed a long time ago.

Lee Jinbum (alias Onkey) - The daughter of Lee Jinki and Lee Kibum. She's intelligent, studious, and devious. Her personality is a mix of her parents, sweet and clumsy one second then aggressive and sassy the next. She looks like her mother with her bow lips and naturally cute face but has her father's eyes. She's been training for her first mission, which her mother keeps delay. Jinbum knows she can handle the outside world but she doesn't know if she'll be able to take down her cousin.