When I was 16, a friend and I were going to make a comic book. Curgoth was the name of one of the villains, a black-skinned, fire-breathing demon with claws who hung out with the team of evil mutants. When I got tired of being "Blood Razor" (one of the heroes) on BBSes, I started using Curgoth instead, and it's stuck over the years. I keep using it because it's unique; there's not another curgoth anywhere.