The Aghoris are known to engage in post-mortem rituals. They often dwell in charnel grounds, have been witnessed smearing cremation ashes on their bodies, and have been known to use bones from human corpses for crafting kapalas (which Shiva and other Hindu deities are often iconically depicted holding or using) and jewelry. Due to their practices that are contradictory to orthodox Hinduism, they are generally opposed by other Hindus.
Some dudes went to Varanasi and spoke to an Aghori Baba and here’s the video. Graphic Content ahead!