Thrasher

Thrasher was found as a puppy by a kind couple who ran a sort of circus. Thrasher was one of the main events of the circus and his job was to demonstrate his strength by various means. As he was mainly raised for the circus, he was never taught the general education that comes with a normal school. Most notably, Thrasher is illiterate. 

Despite being raised to essentially play a part in this circus, Thrasher genuinely loves the couple who found him and regards them as his parents. In fact, having never met another gnoll, he grew up believing that the pair actually were his biological parents, and they didn't have the heart to break it to him.

Still needs to be decided: Why Thrasher was alone ; what the circus was like