|Manga Debut||Round 10|
|Anime Debut||Round 10 (The Fighting)|
|Voice Actor||Okamura Akemi|
Mikami Reiko (三上 玲子) is the daughter of Nishikawa Boxing Gym's trainer Mikami.
Reiko was in a relationship with featherweight boxer Oda Yusuke, who at the time, was being trained by her father. Their relationship was constantly disturbed by Oda's lack of seriousness towards the sport.
One day, while eating at the Chuuka Soba, she overhears Oda's upcoming opponent, Makunouchi Ippo and his friends talking about him. Misunderstanding the situation and believing Ippo to be making fun of him, she decides to not see Oda until he decides to be serious about boxing and defeat Ippo. Her efforts prove to be successful, as her father informs her that Oda has indeed become serious about his training.
Even though Oda loses his fight against Ippo, she does not leave him, but instead is proud of him because of the hard training he did prior to the match and encourages him to keep on fighting.
Reiko is a glasses wearing young woman in her early twenties. She has dark eyes and long brown hair. She is usually seen wearing a shirt and a skirt.