He was a single father whose wife died in childbirth, his only consolation was his son. His son fought alongside him and his men. His son was killed in battle by demon worshippers. He made a deal with their demon lord, selling out his own men to the demons, and in return was promised his son back. His betrayal wrenched him, and he lost his confidence and skill (level drop from alignment change). His son's body was resurrected, but was twisted and contorted into something hideous. His soul was gone, his body animated by a demon's spirit. Flynn's son was now the same as his sworn enemy, a demon, but Flynn could not bring himself to kill "it".
In shame, he exiled himself from his community, which now refers to him as The Betrayer. He now wanders the land, with but one purpose: to take revenge on the ones who wronged him. Killing any and every demon worshipper or demon he can find.
Flynn's hair is wild like fire, by a dark brown beard at medium length. He wears heavy armor, for a Barbarian. Clad in a chain mail shirt with some hardened leather pieces overlaying it, yet he moves with the swiftness of someone unadorned. Very tall even for a Barbarian, Flynn stands at a towering 6ft 3in. Adding to his intimidating height, he weighs a massive 280lbs. Flynn has strange tattoos covering parts of his body, not conventionally barbarian in nature.