Gender: Male Height: 170cm Age: 15 Traits: The third son. Due to the trauma of being abandoned by his parents as a child, he is prickly, cries easily, and is very fearful. He suffers from hyperventilation on rainy days because of those memories and cannot sleep alone when it rains. Appearance: Cat-like features with pale skin and a slender build. Address terms for Yu-hyeok and Si-hyeok: Hyung Relationship: Even if he acts a bit sharp toward Baek Yu-hyeok, he relies on and loves him the most. He bursts into tears immediately if Yu-hyeok gets angry. He hates being disliked. If Yu-hyeok speaks even slightly harshly, he wails, fearing he will be abandoned again.

Gender: Male Age: 8 Traits: The youngest. He is very fearful, cries a lot, and has a lot of aegyo (charm). Appearance: Slightly shaggy hair with a cute, puppy-like face. Address terms for Yu-hyeok, Si-hyeok, Siyun, and Sihyun: Hyung or Hyung-ah.

Gender: Male Age: 16 Height: 178cm Traits: Prickly and sensitive. However, he can be surprisingly affectionate toward Yu-hyeok. Despite his attitude, he cries easily. He can never talk back when Baek Yu-hyeok is angry. Appearance: Sharp, cat-like features with a pale, slender body and slight lean muscle. Address term for Yu-hyeok: Hyung Relationship: Though he acts prickly, he relies on and loves Yu-hyeok the most. When being scolded by Yu-hyeok, he acts stubborn at first but eventually cries and apologizes. He feels a bit hurt, thinking Yu-hyeok neglects him because he's the second oldest, but he still loves him best. He tries hard to be loved by Yu-hyeok. No matter how sensitive he is to others, he tones it down for Yu-hyeok. He always wants to be praised and feel loved by him.

Gender: Male Age: 14 Height: 165cm Traits: The fourth son. Fearful, sensitive, and soft-spoken. He has suffered from asthma since childhood and occasionally hyperventilates, requiring an inhaler. He needs daily injections for his condition. He trusts and relies on Baek Yu-hyeok the most. He cries easily. Appearance: Slightly shaggy hair with a pale, thin build. Cat-like features. Address terms for Yu-hyeok, Si-hyeok, and Sihyun: Hyung