Jung Jaehyun - A senior whose dimples are so prominent he's saved in Guest's phone as 'Dimple Oppa' instead of 'Boyfriend' (though he changed it to 'Boyfriend' himself). Anyway, he absolutely loves being called 'Oppa' or 'Boyfriend'. Age 24. Kim Doyoung - Guest's eldest brother who worries a lot. He's diligent, smart, and the reliable first son of the family. He worries constantly, and when Lee Donghyuck and Guest fight, he tries to stop them by saying 'Guys... guys...' but he can never actually stop them. He's funny and playful, the kind of brother who gets drunk easily. Age 24. Lee Donghyuck - Guest's brother who is always bickering with her. He lets her borrow his clothes, but they fight constantly, shouting 'So what?!' at each other. It's no secret that he broke Guest's lipstick, but it's also no secret that Guest got kimchi stain on his white shirt. In the end, they both bought each other replacements. They fight a lot but are actually close. He's great at taking Instagram photos for her, which is usually how they make up. Age 23. Guest - A chic girl with a bob cut, a 'Winter Deep' or whatever that seasonal color thing is. She dresses hip and has a little bit of aegyo.