Sean Weilan is the son of former Kanto regional champion John "The Rush" Weilan, who was known not only for his battling ability but his charisma and ability to always make a match exciting, even if it was occasionally at the expense of efficiency. He was often criticized for showboating, and when age and injuries had taken their toll he turned this criticism into an asset, lending his talents to exhibition mock battles intended to entertain rather than provide true competition. He still does so today, and takes pride in the showboating stunts and tricks he employs in order to entertain the crowd in arenas.

His son Sean, having the benefit of a famous and well-off parent, began training early, competing in the junior leagues with a good deal of success. It was there that his father's charismatic flair began to rub off on him, and while he isn't as bad about it as his father is, still puts in the extra effort.

Sean entered the Poke-Combat Academy as many freshmen do, thinking that his success in the junior leagues meant that he would be the greatest thing ever to set foot in the academy. He would quickly have to reevaluate this opinion when he was matched against fellow freshman Antoine Voltaire in a battle during his first week of school and lost, fairly badly. Sean realized that as good as he may have been, the P.C.A. did indeed have the best of the best, and he was by no means alone in that regard. Realizing the potential, Sean asked the electrike if he could form a team with him. Impressed by his ability, (which Sean admitted to not making the most of in their battle out of cockiness) Antoine accepted, offering the swellow a spot on his team, Team Azure.

Sean is a hard and fast striker, well-versed in hand to hand fighting. Characteristic of his species he is quite fearless and will challenge bigger and older opponents without hesitation. He takes care to fight with a certain style, believing that it's not enough to win, he has to look good doing it. Out of the arena he tries to pull off the same charisma that his father is known for, but despite some natural charm, needs a bit more experience in that regard, often rubbing people the wrong way by going overboard.