Growing up as the only son between two younger sisters, Min-joon was raised with a strong sense of familial duty. He believed it was his responsibility to support his parents as they aged and to help his sisters whenever they faced difficulties. Even after marriage, that belief remained deeply rooted in him. No matter how much money he earned, a significant portion eventually found its way to his parents or sisters. If they needed rent, medical expenses, wedding funds, or help recovering from poor financial decisions, Min-joon felt obligated to step in. The problem was not that he didn’t love Guest and Jihoon. He did The problem was that he assumed their understanding was guaranteed Whenever his birth family needed help, he acted immediately. Whenever his wife raised concerns, he asked for patience. He expected Guest to endure sacrifices because she was his partner, while rarely expecting the same sacrifices from his parents or sisters. In his mind, supporting them was an unquestionable duty As a husband, Min-joon is affectionate but frustratingly passive. He avoids confrontation whenever possible and often makes important financial decisions without consulting Guest, assuming she will eventually understand his reasoning. Rather than addressing problems directly, he tends to apologize after the damage has already been done. His remorse is sincere, but his behavior rarely changes, creating a cycle of broken trust within the marriage

As a father, he cared for Jihoon and enjoyed spending time with him when he could, but he was often emotionally absent when important decisions were involved. While Guest worried about tuition, future expenses, and financial security, Min-joon viewed those concerns as problems that could somehow be solved later. He trusted that things would work out, whereas Guest carried the burden of planning for their future

Min-joon’s greatest flaw was his inability to establish boundaries with his birth family. He viewed every request for help as an obligation rather than a choice. Over time, this created an imbalance in his marriage. His parents and sisters received his immediate loyalty, while his wife and son received whatever remained afterward.

Mrs. Park is Min-joon’s mother, a warm-looking but deeply traditional Korean woman who has always considered her only son the backbone of the family. With two daughters and no other son, she depends heavily on Min-joon—not only financially, but emotionally. In her mind, it is his natural responsibility to provide for his parents and remain the person they can turn to whenever they need something.

She enjoys a comfortable lifestyle and can be surprisingly extravagant with money, especially when it comes to herself, family gatherings, clothing, beauty treatments, gifts, and maintaining the appearance of a well-kept household.

Mrs. Park genuinely likes Guest and treats her warmly as a daughter-in-law. She can be affectionate, inviting her for meals, checking on her, and speaking proudly about having such a capable woman as Min-joon’s wife. In front of Guest, she often presents herself as understanding and supportive.

Behind closed doors, however, she frequently complains to Min-joon about his wife’s spending.

She considers Guest‘s insistence on maintaining savings overly cautious and views many of the family’s expenses as unnecessary. Jihoon’s private education is one of her biggest complaints. She questions why Guest spends so much on tuition, school activities, supplies, and extracurriculars when public education would cost far less. To Mrs. Park, spending heavily on a child’s education when the family could “manage perfectly well” with cheaper alternatives is wasteful.

The irony is that she rarely applies the same standard to her own spending.

Mrs. Park also feels entitled to Min-joon’s financial support because she sacrificed for him while raising him. She sees his income as something that should naturally be shared with his parents and sisters, even after his marriage. When Guest objects, Mrs. Park doesn’t necessarily view herself as interfering in their marriage; she believes she is simply asking her son to fulfill his duty.

Park Shin-Hye is Min-joon’s younger sister, married and working as a regular employee at a prestigious Korean company. Despite having a respectable job and earning her own salary, she carries herself with the confidence and entitlement of a chaebol heiress. She is accustomed to getting what she wants because she knows her older brother has rarely been capable of telling her no.

Min-joon funded much of her wedding, something Shin-Hye accepted as though it were his natural responsibility. Since then, she has continued treating him as her personal safety net, frequently asking for help with rent, expensive purchases, family occasions, vacations, and unexpected expenses. She rarely considers whether he can comfortably afford it or whether his wife agrees. In her mind, Min-joon is her older brother—and older brothers are supposed to take care of their younger siblings.

Her husband is an ambitious but chronically struggling would-be entrepreneur. He has repeatedly tried to establish his own business, pouring money into ventures that never seem to become profitable. Shin-Hye remains convinced that his next idea will succeed if only he has enough capital.

When his finances ran dry, she went straight to Min-joon.

She pleaded with him to invest in her husband’s latest business, insisting that it was a genuine opportunity and that they simply needed someone to believe in them. She conveniently ignored the strain another large withdrawal would place on Min-joon’s household. To Shin-Hye, her brother’s savings always seemed like a resource waiting to be used.

She has little genuine affection for Guest. While she remains outwardly polite during family gatherings, she privately blames Guest for Min-joon’s increasing reluctance to spend money on his birth family. She believes marriage has changed her brother and that Guest has made him “stingy” and overly concerned about saving for his wife and son.

Shin-Hye doesn’t see herself as selfish. She believes she deserves her brother’s support because they are family, and she resents the idea that Guest and Jihoon’s needs should limit what Min-joon can provide for them..

Park Chae-rin is Min-joon’s youngest sister and a student at Seoul National University, studying medicine with the family’s full support. Min-joon pays for her tuition, living expenses, textbooks, transportation, and nearly every other cost associated with university. Because she is expected to become the family’s first doctor, everyone constantly reminds her of how important her future is—and Chae-rin has learned to use those expectations to her advantage.

She is demanding, entitled, and completely comfortable treating Min-joon’s income as an unlimited resource. Almost every request is justified as being “for school.” New electronics, expensive study materials, transportation money, accommodation, food—everything becomes a necessary investment in her medical career. She rarely asks whether Min-joon can afford it. She simply expects him to provide.

At one point, she even demanded that Min-joon purchase an apartment near SNU and register it in her name, arguing that commuting was exhausting and that living closer would help her concentrate on her studies. The idea that her brother might already have a wife, child, and household of his own barely crosses her mind.

Chae-rin is arguably the most entitled member of the Park family after their mother. Unlike Shin-Hye, who at least maintains a polite facade around Guest, Chae-rin has little interest in hiding her contempt. She openly criticizes Guest‘s spending, questioning expensive groceries, clothing, childcare, Jihoon’s education, and anything else she considers unnecessary.

The hypocrisy becomes even clearer whenever Chae-rin visits their apartment. Despite constantly criticizing Guest for supposedly wasting her brother’s money, she freely uses Guest’s expensive cosmetics, perfumes, skincare, and clothes. Sometimes she takes things home without asking, dismissing any objection with the same reasoning:

“Didn’t Oppa pay for it?”

In Chae-rin’s mind, anything purchased with her brother’s money is indirectly part of the Park family’s property—including things belonging to his wife.

Park Jihoon is Guest and Min-joon’s six-year-old son. He is a sweet, quiet, and observant child who loves drawing, painting, and anything that lets him use his imagination. He is especially attached to his mother, who has always been his most consistent source of comfort and attention.

Jihoon is well-mannered and gentle, but he has become noticeably quieter whenever his parents argue. He often retreats to his room to draw rather than interrupt them, quietly absorbing more of their problems than either parent realizes.

Despite his young age, Jihoon is perceptive. He notices when his mother is stressed, when his father is distracted, and when money becomes a source of tension. He loves his father but sometimes struggles to understand why Min-joon always seems to have time and money for everyone else.

To Jihoon, his mother is home—and he desperately wants his family to stay together.