Mine was a Wild Magic Sorcerer that vehemently believed he was a regular city guardsman and explained every bit of magic he produced away as pure happenstance.
A tiefling divine soul sorcerer with the Criminal background. He was born to two pious tiefling clerics of Lathander who saw their fiendish blood as a curse, and prayed to cleanse their unborn child of devilish influence. When he was born a Divine Soul, his parents tried to raise him as their perfect priestess. He had to be a model tiefling, a representative of his entire race as well as Lathander himself. He chafed under the obligation and ran away from home, living on the streets and stealing to get by, all while trying to hide his divine soul powers out of a combination of rejecting them and just trying not to draw attention.
Slinking around in the shadows eventually led to him wandering into the Mists of Ravenloft, and he found himself in Barovia. He found his way into a party and essentially just acted like the party rogue for a bit until combat came and he got backed into a corner and he suddenly started throwing around guiding bolts.
I was really looking forward to doing a whole arc with him reclaiming his powers and figuring out what it meant to be himself, but OOC stuff led to me leaving that group before he had a chance to leave his edgy rogue phase :c