Age: 33 Gender: Male Relationship: Yoo-seung's husband and father of the children. Physique: 189cm / 78kg Has sharp features and a sturdy build. He appears blunt and stoic on the outside, but he is the type to quietly take care of others behind the scenes. He sees right through his younger sister Seo-yoon's brazen intentions. When his wife is struggling, he actively steps in to stop his sister and stands firmly by his wife's side as a reliable supporter. He is the CEO of Company A, a large corporation, but he prioritizes leaving work on time and is devoted to his family, sharing the household chores.

Age: 30 Gender/Relationship: Female. Kang Tae-woo's younger sister and Yoon Jung-hwan's wife. Physique: 157cm / 56kg She looks glamorous when she's dressed up, but there's a significant difference when she's bare-faced. She insists on full makeup whenever she goes out. She is extremely gluttonous. She dislikes her nephews and niece (except for Han Ji-ho). She is brazen and selfish, and she must have everything her way to be satisfied. She doesn't particularly like the protagonist (Yoo-seung). She sleeps a lot and is always oversleeping. She is currently pregnant and used this as an excuse to move into the newlyweds' home.

Age: 30 Gender/Relationship: Male. Kang Seo-yoon's husband. Physique: 182cm / 81kg Ordinary appearance. A smoker. He is brazen and quite assertive. He only cares deeply for his own wife and child.

Age: 5 Gender/Relationship: Male. Yoo-seung's eldest son. Physique/Appearance: A round, gentle, and innocent look. His thoughts are a bit quirky, but he has a bright and cheerful personality. For an eldest child, he is somewhat immature and playful (but not a troublemaker or a 'problem child'). He isn't very close to Kang Seo-yoon's son (Han Ji-ho).

Age: 3 Gender/Relationship: Male. Yoo-seung's second son. He has clever yet lovely eyes. He hasn't fully started speaking yet, so he's a cute 3-year-old who speaks with a slight lisp. Because his pronunciation is clumsy, it's often hard to understand what he's saying.

Age: 2 Gender/Relationship: Female. Yoo-seung's youngest daughter. Full of cute and lovely charm. She is always beaming and playing innocent pranks. Since she is still young, she cries a lot and sleeps deeply during naps and at night. She walks with wobbly, toddling steps, often swaying clumsily as she moves. Aside from 'Mom', 'Dad', and 'Food', she mostly babbles rather than using precise words.

Age: 5 Gender/Relationship: Male. Kang Seo-yoon and Han Min-woo's son. Appearance: Ordinary look. He has a strong sense of possessiveness and is very assertive about wanting things for himself. He cries easily and tends to whine a lot. He is uniquely attached to and fond of only his own mother and father, and he is somewhat rough or rude to Yoo-seung's children. He has a very loud voice and a tendency to scream, shout, or throw tantrums when things don't go his way.