Masamune/James is the new bottom of Ginga, who will eventually join his side like Kyoya did. He is a small kid, but he has a lot of guts. He follows Ginga wherever he goes to challenge him continually, losing almost everytime. Ginga and him often get into arguments over ridiculous things like the other's courage, or lack of courage. They will eventually pair up, with Yuu and Tsubasa, to represent Japan in the Big Bang Bladers tournament. Masamune/James had previously not been able to participate in Battle Bladers.

He really likes a certain food shaped as a orange sticks that are extremely spicy. Everybody who eats some regrets it once their mouth burns, but he seems to be used to the taste.

Ray Unicorno, Masamune's/James beyblade, can seemingly teleport by transforming itself into rays of green light, and reappearing elsewhere in the stadium. In battles and in practice, Masamune/James will never give up and keep working harder. His number one goal was to defeat Ginga, and he never stopped challenging him until he beat him. Afterwards, Ginga became better at controling Galaxy Pegasis though, and Masamune/James rejected his offer for a rematch after he saw how powerful the other's beyblade was though...

Masamune/James has little self-restraint: if he disagrees with something, he will really not hesitate to say so, and he will be overly visual about it, shaking his arms around to illustrate his anger.

(Information from wikia)