Demons are a wide classification of supernatural creatures which are not Fey. The most common aspect they have in common is the use of mortal souls and life energies as food. Intelligent demons will typical seek to make a deal and get a mortal to willing give up what the demon wants. The unintelligent will just seek to take it. The other aspect they have in common is apparent immortality. Their form can be destroyed, but even when that happens they seem to appear again at a later date. Some mages have consulted with demons because they seem to see time differently than humans do, giving them a glimpse into the possible future and the past while living in the present.