The mashan is a demonic vampire known to the people of India and Nepal. Residing in another dimension, the mashan seldom if ever comes to our world because it is very difficult to find a place where the barrier that separates dimensions is weak enough to allow the demon to pass through. On occasion, a sorcerer, by use of geomancy, will discover such a location and summon a mashan to our world with the intent of binding the demon to do his bidding. This is a very dangerous prospect because if the sorcerer makes even the slightest mistake the mashan will drain him dry of his blood and then immediately set out on a killing spree, spreading plague everywhere it goes. Only prayers said to the god Shiva can send the demon back to the realm where it belongs. Shiva uses his influence and encourages the demon to return of its own accord.

Source: Dube, Untouchable Pasts, 67; Fauna and Flora Research Society, Scientific Results of the Japanese Expeditions, 149; Saletore, Indian Witchcraft, 40; Sarkar, The Folk Element in Hindu Culture, 89-90