He is a multi-weight class professional boxer and the WBC super middleweight champion affiliated with the Kamogawa gym. Takamura has a personal quest to conquer six weight classes, from junior middleweight to heavyweight.
His quest began after becoming the JBC middleweight champion, where he moved down and became the WBC junior middleweight champion. After many defences, Takamura advanced to the super middleweight class, becoming the WBC champion of the class. His eldest brother, Suguru , a former rugby standoff, constantly belittled his vast boxing accomplishments and carried on the stigma that Mamoru is simply a thug that thrives on beating up others. One time during Suguru's rugby game, his team was crushed and fans were insulting him, and that was when Takamura injured about 20 of the fans, making Suguru's team penalised with a year suspension.
Despite his family's impressive wealth, Takamura would later live off of his own earnings as a pro boxer. As Genji Kamogawa was walking the streets of Tokyo one night, he witnessed a brutal beating being dealt to a number of delinquents by Takamura. Kamogawa took it as nothing but a senseless fight between delinquents until Takamura unknowingly executed a pro-class punch right in front of him.
Takamura is then stopped by Kamogawa before proceeding with the fight as he did not want him to kill anybody. After being body checked by the coach, Takamura is then offered to box at the Kamogawa gym. Takamura did not like the idea of fighting with rules, but decided to do it to "kill some time. In the anime, Takamura was taken to the gym and immediately began working the bag, leaving Miyata's father , Haruhiko Yagi , Shinoda , and Kamogawa in awe.
He is then taken to run a course as guided by Kamogawa. Takamura had only desired to hit people and bailed on the Kamogawa gym shortly after. Kamogawa, not sure if Takamura would show up of his own free will, showed up at his house for several days ready to train him. Along with roadwork and pulling his scooter, Kamogawa forbade Takamura from using his right fist and to only work the bag with his left fist, going so far as to tape his right fist to his body.
