Simply because a musician has Satanic themes or lyrics in their music, you can hardly jump to the conclusion that all “the big musicians have a deal with Satan.”
That’s like saying, “I have a black cat, so all cats must be black.” It’s ridiculous.
Satanism is like sex: it sells. It’s really as simple as that. While it is possible that some musicians might actually be involved in the occult, most of them do it just for show. Alice Cooper, one of the granddaddies of shock rock, for example, is a Christian, and though he originally created his persona as a way to escape his religious upbringing, he remained a Christian, and reaffirmed his faith in his recovery from alcoholism.
Most people equate Lucifer and Satan as the same being.
But since when is Lucifer the spirit of music?