Misaki Unasaka is the biological mother of Miri Unasaka in the anime Buddy Daddies. She is a woman whose life has been marked by hardship and poor choices. Before the events of the story, Misaki worked as both a hostess and a singer at a local bar called Snack Stardust, chasing a dream of becoming a singer. During this time, she became involved in an affair with Atsushi Hayami, a mafia boss, which resulted in an unplanned pregnancy and the birth of her daughter, Miri. Hayami deserted her after she became pregnant, leaving her to raise the child alone. This experience, combined with her difficult circumstances, caused Misaki to grow deeply resentful of her daughter. Struggling with poverty and an abusive boyfriend who also acted as her pimp, she became a single mother who was mentally broken by her life. Her resentment led her to abandon Miri, sending the four-year-old girl alone to find the father she had never met on Christmas Eve, an act that sets the main plot of the series in motion.

Misaki is portrayed as a complex and tragic figure. She is fragile and vulnerable, yet also hardened by her suffering. Her primary motivation is initially her own survival and the pursuit of her singing dream, which she prioritizes over her responsibility to her child. She is shown to be neglectful and emotionally unavailable, refusing to take responsibility for Miri when the assassins Kazuki Kurusu and Rei Suwa attempt to return the girl to her. However, a significant turning point occurs when Misaki receives a cancer diagnosis. This revelation forces her to confront her life and priorities, making her realize that what truly matters to her is her daughter. In her final days, she undergoes a dramatic change of heart, seeking to become a good mother and spend the remainder of her short life happily with Miri. She hides the scar from her cancer surgery with a scarf, a detail that hints at her private struggle and desire to maintain a sense of dignity even in difficult circumstances.

In the story, Misaki serves as the catalyst for the central family dynamic. Her abandonment of Miri is what brings the child into the lives of the two assassins, ultimately transforming their existence. Her role is that of a supporting character whose actions and subsequent decline create the emotional stakes for Miri's future. Her key relationship is with her daughter, Miri. This relationship is initially defined by neglect and bitterness, but it eventually becomes the focus of Misaki's regret and her desire for redemption. Her other significant relationship is with Atsushi Hayami, her married lover who abandoned her, and later with her abusive boyfriend, who represents the cycle of toxic relationships she is trapped in. Her development is a poignant arc from a resentful and neglectful mother to a terminally ill woman seeking forgiveness and a final, meaningful connection with her child. Her notable ability is her talent for singing, a skill she uses in her work and which she passes on to Miri, who cherishes the memory of her mother's voice.