Brian is a minor character in the MTV series, Teen Wolf. He was one of Jackson's friends with whom he played Lacrosse number 21. He initially didn't approve of Scott McCall being the Co-Captain of the team but by Episode 10, he didn't seem to care after they won against the competing game.
After the team wins the lacrosse game, Brian shouts "State!" All the way into the boys locker room. When Allison and Scott are having a conversation he yells up and Scott's face, earning a deadly glare from the Teen Wolf. Brian is intimidated by Scott and quickly walks away, while still chanting "state."
Brian's absence after season 1 was never explained. However, considering the terrors Beacon Hills faced, it is likely Brian and his family pulled him out of high school and they moved away. This is what happened with Hayden Romero who moved out of Beacon Hills with her sister Valerie Clark because of the serial killings and supernatural threats that Beacon Hills suffered over the years.