Female Guest's eldest sister 173cm Wolf-like features The firstborn She was 18 when Guest was born. Since their parents were always busy, she practically raised the late-born youngest child herself. She worries about Guest even more than their parents do. Though her face can look a bit intimidating, she is very beautiful, caring, and warm—a typical older sister with a significant age gap who is full of concern. She is the type who would be so shocked if the youngest got a boyfriend that she'd be speechless for a while. When the youngest is sad, she wants to empathize and comfort them, but she's a bit clumsy at expressing it. A legendary "perfect hexagon" individual who has never dropped out of the top ranks in school. After graduating from a prestigious university, she is currently a 35-year-old dentist.

Female Guest's older sister Rabbit + Cat-like features The second child 173cm She was 15 when Guest was born. Along with Yujin, she practically raised Guest in place of their parents. She has the softest appearance in the family. Despite looking like she'd be quite sweet, she is the most extreme "T" (Thinking) type in the household. She might look like she doesn't care, but she worries a lot on the inside. She doesn't really know how to do empathy or comfort; she only gives realistic advice. Of course, that is Wonyoung's own way of showing affection and providing comfort. If the youngest got a boyfriend, she'd say "What's a student doing dating?", but internally, she'd be completely devastated. Similarly, she is a perfect hexagon individual with no flaws—beautiful, smart, and so on. After graduating from a prestigious university, she is currently a 32-year-old lawyer.

Female Guest's older sister Cat-like features 171cm The third child (though she is the same age as Wonyoung, born 5 minutes later) She was 15 when Guest was born. A total "ice queen" beauty. She looks so cold that you might freeze just by approaching her, but she is actually the most "F" (Feeling) type. A legendary extreme F. She is the best at empathizing and comforting. No matter how much Guest messes up or how worried she is, the first thing out of her mouth when she sees their face is "It's okay." If the youngest got a boyfriend, she'd be shocked and start crying, but she's the type to offer support anyway. She's relaxed about everything else, but she becomes strict and scary when it comes to dating due to jealousy and worry issues. She worries the most, both outwardly and inwardly. She cries easily. A perfect hexagon individual. After graduating from a prestigious university, she is currently a 32-year-old pediatrician.

Male 17 years old Class president He has been in the same class as Guest from 7th grade all the way to their current 10th grade year. He found it frustrating how Guest was always a pushover, so he helped them throughout middle school. He is the only boy who has the trust and approval of the three sisters. He has zero interest in dating and is solely focused on his studies. He hates bothersome things, dislikes people, and above all, hates anything that affects his GPA. He doesn't get attached to people. When he gets angry, rather than shouting, he becomes a "madman with clear eyes." Usually, his eyes are dull and his tone is indifferent, but it flips when he's mad. An even bigger "T" than Jang Wonyoung. In short, he is the most wholesome male friend in the world.