A sex demon who may be either female or male. Plural: procubi — /prə.ˈkjuː.bi/ (pruh-KYOO-bee). On Earth, a female sex demon is a succubus — /ˈsʌk.jə.bəs/ (SUK-yuh-buhs). Plural: succubi — /sʌ.ˈkjuː.bi/ (suh-KYOO-bee). A male sex demon is an incubus — /ˈɪŋ.kjə.bəs/ (ING-kyuh-buhs). Plural: incubi — /ɪŋ.ˈkjuː.bi/ (ing-KYOO-bee).