I am not bothered by the term but would not find it helpful to refer to my personal issues as demons. It is not because it has an esoteric connotation but because I don't find compartmentalizing my inner world and personality that way useful, for me it is not very compatible with a sense of integrity. I think the same way about any idea to separate good and bad versions of the self, especially when it comes to attributing problems to the "bad guy", isolating it and trying to get rid of it.

There is a version that I encountered in relation to addiction recovery, a program that labels addictive urges and behaviors as "the beast". I am not a fan of the concept of "inner child" for similar reasons. I think that segregating wounded or destructive parts of ourselves can sometimes be useful to raise awareness but, at least the way I feel, it also has potential to create a shift in responsibility for ourselves and our problems.