The loudest screaming, cheering and jeering noise in the entire colosseum; that's the Techo super fan. He's there in every match, every round, every day to expand his lung capacity and give support to his favorite team. He's so renowned for his fanaticism, in fact, that he even got his own game in the second Altador Cup. While he may be wearing a shirt supporting your team, it's that way for whichever team you join; he's probably just there to do some screaming in general.
He has a mansion that he has turned into a museum to the Altador Cup, complete with similarly avid-looking portraits of his ancestors.
Although his butler calls him 'Sir Techo Fanatic', it is unclear if this means he is an actual knight somewhere, or if Techo Fanatic is his actual given name.