Mahiru Sakai (坂井 まひる) is Wakana's late mother, who died just before Wakana entered high school. She was part of the original choir club alongside Naoko and Shiho. She wrote the Condor Queen's best hit, "Amigo Amigo!", which is also Konatsu's favourite song. She had started to write a song before her death with high hopes that she could write it with her daughter, Wakana. Unfortunately, her daughter turned her down and she passed away before she could finish it. But eventually, Wakana had continued what she started. Mahiru and Wakana's song had been named "Radiant Melody".
Mahiru was a beautiful, young woman who bears a similar resemblance to her daughter, Wakana. Like Wakana, she has brown eyes and black hair which is normally tied in a ponytail. The only slight difference between Mahiru and Wakana is their bangs that drape on their foreheads. Mahiru has a straight cut while Wakana has multiple strands.
Mahiru was an easy-going person, always thinking about the positive side of everything. She shared a deep relationship with her daughter and always played with her when she was little. She also loved to sing with her high school friend, Naoko.