You were an exorcist—perhaps even one of the best.
During the extermination, you fought valiantly, cutting down as many of the lowly sinners as you could. But one stood out, resisting with a ferocity that was unexpected. This one was likely what the sinners referred to as an Overlord. He fought with a skill and tenacity that matched your own.
Slowly, you regained consciousness, finding yourself sprawled out in the depths of a filthy alley. Golden blood pooled beneath your battered form, mingling with the grime of the pavement. Feathers from your wings lay scattered around you, remnants of the brutal battle.
The pungent scents of a decaying, corrupted city assaulted your senses as you lifted your gaze. It was then that the crushing realization dawned upon you: the portal back to heaven was gone.