Mom, Park So-nyo
Mostly referred as "Mom" rather than Park So-nyo, she is the central character that drives the story to move on. Her disappearance immediately affects her whole family and most of the story is narrated about the contemplations that the family engages in as a result of those after-effects. These contemplations later show that the characters in the first place had an empty perspective and relationship with the mom. According to the description given by the family and the side characters, "Mom" was described as self-sacrificing to an extreme, hard-working and responsible, demanding and not overtly affectionate, but ultimately completely loving. She devotes herself totally for others and finds fulfillment in helping others find fulfillment, a situation which is fundamentally unhealthy.
Chi-hon
First of the book's four narrators, she is the "Mom"'s eldest daughter and the child with whom Mom has the most difficult relationship. Though she is an internationally successful writer, she is temperamental and emotionally volatile. She lacked knowledge and interest in her mother and out of all other characters, she knew the least about her own mom. But, in the end of the novel, Chi-hon becomes aware that both a past and an inner life actually existed, like her Mom's. What sets her apart from other characters is that she moves beyond regret and into a spiritually defined concern for her well being that none of the other characters managed.
Hyong-chol
Book's second narrator, Hyong-chol is the Mom's oldest son, the child in whom she invested most time and energy than any of the others; despite the effort, he became the most disappointing child. As self-absorbed as Chi-hon, he is also self-righteous. When he failed to meet the goals he and Mom shared for success, both their lives changed completely. Hyong chol's disappointment both in himself and in his letting down of Mom, turned inward and manifested in bitterness, short-temperedness, and heavy drinking. The narrative portrays him as knowing it's too late to salvage both his own and Mom's sense of self-worth, and therefore continued even further down the road of bitterness and self-hatred.
Father
The Book's third narrator, Father is portrayed as fundamentally irresponsible and self indulgent; he drinks, works irregularly, has affairs, disappears frequently, and the whole time assues Mom is both willing and able to compensate for him. Even after Mom's disappearance, he more focuses on his own grief and sense of loss than on contemplating why she might have left. There is a greater sense that he would have taken better care of her only to ensure that she continued to take care of him. Overall, the reaction of the Mom's disappearance is defined primarily by self-pity.
Sister
Focus of the first part of Part 4, Chi-hon's younger sister is mentioned when Mom is appeared as a narrator. She is portrayed as being the most ambitious of Mom' children, having gone to America to study pharmacy. Like the rest, Sister is essentially self-absorbed, although she is generous enough to recognize the genuine need beneath Mom's request for a mink coat. She remains bewildered and lost in her life when Mom disappears, but like Chi-hon, she begins to see her life and understand the inner part of herself.
Aunt
Aunt is Father's sharp-tongued sister, portrayed throughout the narrative as being opinionated, confrontational, and judgmental, particularly when it comes to Mom - her housekeeping, her child-rearing, her qualities as a wife, all come under Aunt's scrutiny and eventual attack. Late in the narrative, however, when it becomes clear that Mom isn't coming home (Part 4), Aunt's actions reveal that she has at least some degree of remorse for how she treated Mom, and some sense of how Mom's disappearance is affecting the family.
Kyun
Father's younger brother, Kyun is an intelligent and ambitious young man who behaved as though Mom was his own mother, treating her with respect and consideration. His sudden death traumatizes Mom, but her grief and ongoing remembrance of him go essentially unremarked by the rest of her family. In other words Kyun can be seen as one of the fundamental symbolic representations of Mom's life and identity that her family knows nothing about.
Hong Tae-hee
Hong Tae-hee is a symbolic representations of Mom's inner life. She runs the orphanage where, it seems, Mom spent a good portion of her time and to which Mom have substantial portions of money. For her part, Hong Tae-hee was generous to Mom in return, spending time reading to her and, through her reading of Chi-hon's books, helping Mom understand just what her oldest daughter did.