He is an embalmer and it is his duty to ensure that the dead are properly prepared for their journey.
He lived a cloistered life, and was basically forced to leave the temple to see the world by his high priest. He was told that he must learn of this world in order to better understand how his god and church fit into it if he wants to advance. Of course advancement isn’t his goal in life, but he accepts the high priest’s words. If it will make him better in the service to his god, then he will do it.
I haven’t decided much beyond that. He will be Egyptian, since we’re most certainly going with a racial theme for this game. Bald as well. Likely tall and wiry, an Egyptian nerd. I’m not sure at all if he’ll be analytical/trusting, shy/outspoken, brave/cowardly... none of that.