Drake is the avatar of Kiaraz, the God of Night.  He was raised in the High Temple of Mandra, in secret, for the purpose of growing up to be the Covenant's physical protection as all the avatars before him had been.  However, the idea of lifelong servitude to a bunch of whacky preists and preistesses with their little political dramas didn't really appeal to Drake.  So, at a young age he ran away from the Temple and struck out on his own - learning quickly how to beg, pickpocket, con, and work for his food and shelter.  Before long he ran into Thelonius and the two of them started travelling together, neither one wanting to settle down and be caught.  They have since lived the rogue's life - wandering from place to place and earning their way either honestly or dishonestly with little care.  Drake's life becomes complicated, however, when he meets Rhonwen and Kamaria and things completely change for him.