|Hair||Light Brown (Normal)|
|B-Daman||WBMA Proto 01 (Normal)|
|Japanese Voice Actor||Yuuko Sanpei|
|English Voice Actor||TBA|
While possessed by Dragold, Ryuji was considered the main antagonist of the first season.
Ryuji is a short preteen boy often seen with a kind expression on his face. He has a short light brown hair and green eyes. He wears a white jacket with red sleeves and black collar. Underneath, he wears a light blue shirt. He also wears dark blue pants that reach up to his ankles and that which has a yellow handkerchief in its pocket. Lastly, he wears a pair of predominantly yellow sneakers.
While possessed by Smash=Dragold, Ryuji's light brown hair blazed into spiky blonde and in his face is now noticeable over-confidence.
In his debut all up to the events leading up to that incident in the Sumadora Ruins; Ryuji is an optimistic boy with great admiration for Kakeru. Ryuji would even go as far as to dare the blizzards of the Northern City just so that he can follow up to Kakeru. Despite that, Ryuji is not a regular fanboy because he, himself, is a highly-skilled player as he had exhibited during the West City Grand Prix and in the Park Exhibition Match against Kakeru and Shuumon.
However, deep within Ryuji's idolatry for Kakeru lies intense jealousy over the fact that Kakeru has a cooler B-Daman and that Ryuji himself had already desired having his own Dragon-Type B-Daman. When Ryuji lost his Proto Zero One inside the ruins, he was totally consumed with the feeling of despair. This is when the spirit of Smash=Dragold took advantage of him.
Under the influence of Smash=Dragold; Ryuji is easily said, a power-tripper. He had discarded his bonds with Kakeru and the others while accepting Naoya as his henchman. Eventually, Ryuji also discards Naoya so that the former can take over the W.B.M.A. himself. Ryuji's power-tripping is partly because of Dragold's influence and Ryuji's own jealousy towards Kakeru.
- His family name "Sumeragi" is Japanese for Emperor while his given name "Ryuji" means Dragon. Altogether, Ryuji Sumeragi means Dragon Emperor. This is fitting for his Dragold-possessed persona.