In the Talmud and Christian demonology, the demon king associated with lust is Asmodeus.
Asmodeus, also called Ashmedai in Jewish tradition, is presented in Talmudic stories as a king of the shedim, or demons. He is also a major figure in the deuterocanonical Book of Tobit, where he attacks the marriages of Sarah by killing her successive husbands before they can consummate the relationships.
His connection with lust became especially prominent in later Christian demonology. The 15th-century Malleus Maleficarum identified Asmodeus with lust, and later demonological systems described him as a prince or king of Hell. This association helped distinguish him from figures such as Satan, Belial, and Beelzebub, whose roles vary across religious and occult traditions.
The Talmudic Ashmedai is not identical in tone to every later Christian depiction. Some Jewish tales portray him as clever, humorous, or involved in the legends of King Solomon and the building of the Temple. Thus, “demon king associated with lust” is a later layered description rather than a single uniform portrait across all sources.