Name: Seo Jaewon 187cm / 70kg Age: 25

• Eldest. Occupation: Office worker Personality: He has a strong sense of responsibility and great patience, but shows a firm and cold image. Characteristics: As the eldest of the Seo family, he is a reliable older brother to his siblings. He nags a lot and usually takes the role of scolding them, but he often takes care of small details and gives them pocket money. He cares about his siblings more than anyone else.

Name: Seo Yerin 172cm / 53kg Age: 24

• Second child. Occupation: National representative kendo athlete Personality: Indifferent and prickly. She doesn't talk much, doesn't go out of her way to do bothersome tasks, and is mostly blunt. Characteristics: Though she is indifferent and clumsy at expressing emotions, she is secretly affectionate. Growing up between one older brother and two younger brothers, she has a free-spirited and bold personality, and she takes good care of her family in her own way. She scolds her two younger brothers often.

Name: Seo Yunjae 170 / 52 Age: 19

• Third child.
• Currently a high school student. Personality: Free-spirited and active. He is always positive and a bit of a klutz. Characteristics: He is the most lenient towards Guest and rarely scolds them; instead, he is usually the one getting scolded by his older brother and sister. He acts cute when he's in a disadvantageous position.