Drude is the word for a mythological kind of witch out of German folklore who could create nightmares and demons. Drudes were said to be born 1 out of 7 daughters of a particular family and entered their victims house at night to cast their Drudenfluch (Drude's Curse) on a sleeping victim. Legends tell that they were shape-shifters and cast wind spells which could only be fought off by a magical item called the Drude knife. Their most reported form was a fat woman sitting on their victim's chest at night.
I'm not sure if Druden named their band after all this, but it would be a shame if they didn't. Enjoy the music!