Bai Qingyue was not unfamiliar with acts of torture. Unlike in popular myths, deities were not all kind, righteous beings who led the rest of the population by example. The Celestial Realm had its own rules and leadership; karmic retribution was ordained by the heavenly energies governing all living entities.
However, that was not to say that the gods did not inflict punishment upon each other, or upon mortals – certain deities were actually appointed to do just that. There were divine punishments meted out frequently, and naturally the ones in charge of condemning criminals in the upper planes were the Sovereign Lords of each celestial tribe.