Mai Osamu is the daughter of Joe Osamu and Chan Lee. She is a Pyrus brawler partnered with Fortress, and a member of the Earth Division.
Mai is 12 year old human girl. She has long, black hair that she keeps tied into two braided pigtails with ribbons, and grey eyes.
Mai has a natural instinct to protect her friends and family, especially her older brother since he is not a brawler nor a martial artist, like herself. Mai is a very kind and caring young girl, often trying to nurture or mother her friends, albeit unsuccessfully, when she's not trying to protect them.
However, Mai is also a show-off. She likes to show-off whenever she gets the chance, especially if it's proving someone wrong. This can make her overconfident and oftentimes she underestimates her opponent, which has her land herself in a heap of trouble. ...This is why her brother constantly keeps an eye on her, because, despite the fact that she protects everyone, she doesn't realize that she may need some protecting herself.
- Father: Joe Osamu
- Mother: Chan Lee
- Older Brother: James Osamu
Jamie and Mai are a very close pair of siblings. They both try to protect each other, and Jamie can contact Mai during her brawls to help her.
Mai first met Teddy when she saved his life, and ever since then, Teddy has had a big crush on her. Mai constantly supports Teddy and enjoys his music, which only furthers his crush on her.