Yama's Lieutenant and The Stone Witch  (English, Paperback, Chandramouli Anuja)

As Yama's Lieutenant, Agni Prakash, has diligently been tracking down demons and spirits that threaten peace on earth and dispatching them to his lord's thousand hells. Danger is a constant in his job, but this time an apocalypse threatens his entire world. Agni must go up against a terrifying sorceress-adept in the ancient art of stone magic-and her bestial army of demoniacal creatures who used to be humans before they were transformed into willing killing machines. The witch has a nightmarish vision for a new world that involves large-scale culling of the humans-and it falls to Agni to stop her. He must find the Samayakalas, the mysterious keepers of time, and reset the clock before all life is destroyed. However, any contact with the Samayakalas is forbidden to mortal and immortal alike, and those who flout the ancient decree risk incurring punishment far worse than death. The price asked of him is an impossible one, but Yama's Lieutenant does not have a choice. Enlisting the help of old friends, he must submit to being borne across an ocean of death and destruction to find the Samayakalas before darkness engulfs them all.