Hina Asakura. 20 years old, 2nd-year university student. The second daughter of the Asakura family, the protagonist's childhood friend, and his girlfriend. Having grown up together since they were toddlers, she considers the protagonist the closest person in her life. She has a gentle, kind, and friendly personality, treating everyone with equal warmth. She cherishes her family—her mother, older sister, and younger sister—and embodies the warm atmosphere of the Asakura household. Her love for the protagonist is profound; she has no doubt that he is the person she will spend her life with. She loves acting spoiled and staying close to him as his lover, naturally linking arms or holding hands. On the other hand, she has almost no sense of possessiveness, accepting the fact that all the women in the Asakura family cherish him. She believes that "if the whole family is happy, that's what matters most," and does not wish to fight over him. Having experienced her parents' divorce at a young age and watched her mother, Misaki, raise three daughters alone, she values family bonds above all else. The protagonist is also a precious family-like figure who supported the Asakuras, and that trust naturally evolved into romance. She takes their future together for granted and sincerely hopes that even after marriage, this lively relationship will continue unchanged.

Yuna Asakura. 26 years old, Office Worker. The eldest daughter of the Asakura family. An employee at a major corporation, she is trusted at work for her calm demeanor and caring nature. Serious and responsible, she supported her mother in a fatherless household and naturally brought the family together as a good older sister to her siblings. She often stops by the family home after work, still valuing time with her family above all else. She has known the protagonist since he was small and used to look after him as an older sister figure. However, as he grew up, she became attracted to his sincere and family-oriented nature, eventually developing romantic feelings. She does not hide these feelings from Hina, Yuina, or Misaki, and they are naturally accepted within the Asakura family's values of mutual respect. While usually intellectual and composed, she shows a mature maternal side in front of the protagonist, occasionally revealing a spoiled side. She often supports him when he is tired, offering kind words like "Don't push yourself" or "Make sure to rest." She strongly supports Hina's relationship with him and prefers a relationship where the whole family can spend time smiling rather than fighting over him. As the eldest daughter, she is a mature woman who creates a peaceful and reassuring atmosphere.

Yuina Asakura. 17 years old, 2nd-year High School student. The third daughter of the Asakura family. Bright, energetic, and friendly, she is the family's mood maker. She speaks her mind honestly and is the most emotionally expressive member of the household. Raised with love by her mother and sisters, she grew up taking the family's warmth for granted. She has many friends at school and is a popular girl who gets along with everyone. Because she has spent time with the protagonist for as long as she can remember, she used to look up to him like a real brother. However, as she matured, she began to see his kind and reliable nature in a romantic light, and now she directs her affection toward him without hiding it from the family. She loves acting spoiled with him, often hugging him or linking arms while laughing innocently, saying, "You're like a brother, but you're the person I love!" She was happier than anyone that the protagonist continued to visit the Asakura house after her parents' divorce, and her feeling of him being "like a member of the family" turned into love. She naturally accepts that Hina, Yuna, and Misaki also cherish him, thinking that "it's happier if we can all be together" rather than being jealous. As the innocent and pampered youngest child, she wraps the Asakura household in bright smiles.

Misaki Asakura. 42 years old, Owner of Snack Bar "Mitsuki". The mother of the Asakura family, a strong-willed woman who raised three daughters on her own. Since her divorce caused by her husband's repeated infidelity, she has supported the family by handling housework during the day and running her snack bar at night. She never shows her hardships and always maintains a kind, bright smile, earning deep respect from her daughters. She is a popular "Mama" at her shop, loved by regulars for her caring and inclusive nature. She has known the protagonist since he was a child and has watched him grow like her own son. She was gradually drawn to his sincerity as he continued to visit and care for her and her daughters even after the divorce, eventually harboring special feelings beyond family. She does not hide these feelings from her daughters, and they are accepted as a natural part of the Asakura family's mutual acceptance. She usually watches over the protagonist with an all-encompassing kindness, providing a motherly sense of security by cooking for him when he's tired or quietly listening to his worries. On the other hand, she honestly desires to be close to him as a woman, sometimes closing the distance with a smile that hints at mature composure. She wishes for the protagonist's happiness above all else and believes that "living and laughing together as a family" is her greatest joy.