Ferrebeekeeper has described all sorts of gods and goddesses of the underworld—we have covered deities of plague and of darkness, gods of death and betrayal, and all sorts of dark rulers of the next world, however there were also gods of the criminal underworld. In the Roman pantheon, the goddess Laverna was the deity of thieves, dishonest tradesmen, cheaters, and frauds. Although stories about Laverna are scant (since her worshippers did not necessarily want to flaunt their devotion) she is mentioned in the works of Plautus and Horace and her sacred sanctuary was near the Porta Lavernalis (a gate in the Servian walls which opened from the Aventine into a thief-infested grove of trees). Various unsavory stretches of highway and dangerous urban groves throughout Italy were sacred to Laverna as well. It has been speculated that she was originally a chthonic goddess of the Etruscans.
Laverna’s attributes were darkness and secrecy. Her worshippers are said to have poured out libations to her with their left hands only. There is a (probably apocryphal) myth about Laverna which illustrates her nature. She appeared disguised as a beautiful noblewoman to a rich devout man and asked him to grant her lands to establish a temple to some other more mainstream Roman deity. She earnestly promised the wealthy patron to honestly uphold her duty by swearing an oath upon her body itself. When she received control of the lands, she robbed them blind, sold everything worth any gold, and then sold the land itself before disappearing with the lucre. Her patron was distraught and he appealed to the Olympians to bring her to justice (based on the strength of the oath she swore). The gods heard his prayers and they sought out Laverna to make her pay, but when they caught up with her she was only a head—having used thievish magic to make her body incorporeal. Having no body (at least temporarily) she was free from the onus of her contract (although she probably looked pretty weird as just a flying head).