Yuuma is a calm and serious person. As a child, he and Fumina promised to enter the World Tournament together. However after a brutal defeat, Yuuma was traumatized and as a result began to see Gunpla Battle as a pointless sport. So he decided to quit and take up artistic Gunpla building instead. But as Sekai Kamiki commented, he still desired for Gunpla Battles, and to fulfill his childhood promise with Fumina.
After joining the Try Fighters, he is beginning to overcome his conflicting feelings about Gunpla Battling and now devotes himself to winning with his team. He has shown a more critical and serious outlook when it comes to Gunpla Battles which is primarily shown by his constant bickering with Sekai Kamiki.
Yuuma is known for his exceptional skills in Gunpla building and Gunpla Battle (especially as an expert sniper). Mr. Ral states that Yuuma is one of the very few to have ever made him drop his shields.