succubus vs demon

succubus and demon both are nouns.

Word	Noun	Adjective	Verb	Adverb
succubus	Yes	No	No	No
demon	Yes	No	No	No

As nouns, demon is a hypernym of succubus; that is, demon is a word with a broader meaning than succubus:

succubus: a female demon believed to have sexual intercourse with sleeping men
demon: an evil supernatural being

Other hypernyms of succubus include daemon, daimon, devil, fiend.

succubus (noun)	demon (noun)
a female demon believed to have sexual intercourse with sleeping men	an evil supernatural being
	a cruel wicked and inhuman person
	someone extremely diligent or skillful