When Kaal Bhairav was charged of Brahma Hatya, he came to Kashi to seek penance and it had been only in the holy land of Kashi that he was at last free from your sin of the killing. From that point on, Kaal Bhairav is said to reside in Kashi, https://felixsusqo.blogsumer.com/29627985/bhairav-an-overview