Various noxious stinks, tending to be sulfur in nature, are created by ghosts, poltergeists, demons, and other higher dimensional entities. Although gentle ghosts, usually relatives, tend to leave behind pleasant aromas such as perfume or cologne they wore in their time alive on Earth. The wretched fumes generally come into existence from a nefarious spirit whose sinister thoughts translate into dark metaphysical energy. That enchanted energy moves into our reality to become energy strings whose vibrations create a domino effect of sub-atomic and then atomic matter.
For reasons not fully understood Hydrogen and Sulfur are the ones most commonly produced. However, Hydrogen was the first element in our Universe at a time when only higher dimensional beings existed. Not to mention that Sulfur is also known as Brimstone. The most common element in the Underworld aka Physical Hell! The two elements mingle together to form molecules of Hydrogen Sulfide which is responsible for the tell-tale rotten egg sulfur stenches that various non-corporeal paranormal entities are infamous for. More than likely this is a design of Mother Nature to warn us of various paranormal perplexities👻