"Indeed, he [Satan] and his tribe see you from where you do not see them. We have made the devils allies to those who do not believe."

“Dan shall be a serpent in the way, a viper by the path, that bites the horse’s heels so that its rider falls backward.”

"Demons too can appear in human form… the fact someone looked human is no proof it's not a demon."

Talmud: Hagigah 16a

''they eat, drink, multiply, and die like human being'' - Talmud