For most of its lifetime, Dungeons and Dragons has had demons and devils among its monsters. Briefly, in an attempt to avoid criticism as "satanic," the serial numbers were filed off and they were renamed as the none-to-evocative Tanar'ri and Baatezu.* In a similar vein, the art on the Magic: the Gathering card "Unholy Strength" had its pentagram airbrushed off when it went mass-market.
Both decisions were later reversed.
Now Wizards of the Coast has gone entirely in the other direction. In their new collectible game Hecatomb, you play endbringers, folks who summon abominations to harvest souls and bring on the end of the world (first one to end the world wins).
Well, then. :)
The nice clerk at Pegasus Games said it's not doing terribly well yet, and didn't like it himself, equating it with a junior high kid trying for shock value.
*This was misguided, anyway. The criticism was never based on the presence of demons and devils among the characters' enemies. The folks who think roleplaying games are a significant social evil that matters more than, say, hunger, take issue with characters that can cast spells and that kind of thing.