Honestly, I read that the religion insists on celibacy, and I stopped reading.
However, looking into it, the character abandons the religion. In my backstory, he leaves home at an early age to live among the stars. It honestly could fit if you wanted to play around with the Executive Sister NPC.
I would change the backstory to mention being adopted, then getting a job on a transport starship to get away from the family and the religion.