Camazotz

In the Popol Vuh, Camazotz are the bat-like monsters encountered by the Maya Hero Twins Hunahpu and Xbalanque during their trials in the underworld of Xibalba. The twins had to spend the night in the House of Bats where they squeezed themselves into their own blowguns in order to defend themselves from the circling bats. Hunahpu stuck his head out of his blowgun to see if the sun had risen and Camazotz immediately snatched off his head and carried it to the ballcourt to be hung up as the ball to be used by the gods in their next ballgame.^[3]

In Part III, chapter 5 of the Popol Vuh, a messenger from Xibalba in the form of a man with the wings of a bat brokers a deal between Lord Tohil and mankind, wherein mankind promises their armpits and their waists (the opening of their breasts in human sacrifice) in exchange for fire.

From :wikipedia