Kazuma Ikezawa

Kazuma Ikezawa - The 13-year-old cousin of Natsuki Shinohara. His avatar is King Kazma, a renowned martial artist in the World of Oz. Kazuma is also a hikikomori who seldom leaves his room and uses his talents to win every game in Oz. But it's hinted that he does have friends, as more a spin-off manga made after Summer Wars telling about how he was able to become King Kazma. When he is not in his room, he trains in Shaolin Shorinji Kempowith his grandfather, Mansuke Jinnouchi.

The Miracle Elite Adventures
TBA

The Guardians of Cosmictopia (Non-Canon)
Kazuma teams up with Strong Bad as they're both geeks.