Agon Kongo (金剛 阿含, Kongō Agon) is a utility player of the Shinryuji Naga The younger of twin brother Kongo Unsui, Agon is considered a one in a million genius player for whom the sport comes naturally - not least of all by himself - and treats everyone other than himself as worthless trash. However, he is forced to come to grips with his own arrogant ways and feelings when he faces the Deimon Devil Bats in the Kanto tournament playoff, particularly the trio of Yoichi Hiruma, Ryokan Kurita, and Gen "Musashi" Takekura, of whom his actions allowed them to form a rival football team in the first place.

The Kongo twins are like chalk and cheese - not only in ability, but also in attitude and personality. Agon Kongo is lazy, arrogant, vicious, invariably turns up late to the matches - often in the second half - and never ever trains, yet his skill is incredible. He is also a chauvinist who does not take rejection well, since when Mamori rejected his advances on the bridge he threw her on the ground and advanced on her, although he made it look afterwards like an accident. Even though Unsui is a solid player, whose skill has come from constant hard work, Agon's abilities go far beyond even the best. Kumabukuro, the reporter, says that he has tremendous talent that is only seen once every 100 years. Even the Nagas coach wants everybody in the team not to act the way he does, and tells them that only Agon has the leeway to act in this manner. This is because Agon's natural talent is near-superhuman, and allows him to do whatever he wants. This has made him arrogant and over-confident in his ability. He looks down on everyone else - even his own (older) brother, whom he calls "Unko-chan" as if to scorn him (effectively a tautology, as he's calling Unsui small twice - lit. "Little Unsui the Child". "Unko" is also a childish way to say 'Shit' or 'Dumping' in Japanese, effectively calling Unsui a 'little piece of shit'). Initially, he displays his agility to Sena and makes a powerful bullet pass at Torakichi (still in his wheelchair), who teases their team but luckily is saved by Sakuraba, Monta and S