Ekimmu means The Seizer from ekemu - to seize. Ekimmus were referred to as the evil gusts of wind.
The edimmu were also thought to be completely or nearly incorporial, "wind" spirits that sucked the life out of children and the sleeping.
A person could become an ekimmu
Ekimmus are extremely vengeful toward the living. They may cause disease and inspire criminal behavior in the living. Sometimes ekimmus attach themselves to any living person, regardless of the fact they had been acquainted with the dead one or not.
They were said to be able to possess those who did not take into account certain taboos, like not to eat ox meat. This theory is also upheld by the fact that the Assyrians believed the Ekimmu could walk through doors and walls, like spirits.
Ekimmus were said to be the bringer of misfortune and death to its victims and their households. Its howling in the night warned the living of an impending demise.
Ekimmus are very difficult to eradicate through exorcism. Sometimes they can be appeased by funeral repast.
Ekimmu’s origins date back 4000 BC. Originally they come from the Assyrians, then later shared by Babylonians, as well as interpreted by the Inuit and Eskimo tribes. A thousand years later they were feared by the Mesopotamian Empire, where the creature was believed to be an angry spirit unable to find peace. In Sumerian mythology utukku were a spirit or a demon, that could be either benevolent or evil. The evil was known as Edimmu or Ekimmu. The good ones were named Shedu. Utukku were supposed to do the will of Anu, the god of the Heavens. There were utukku of the plain, the mountains, the sea, and the grave.
Assyrians believed that after death a soul would enter the Underworld. There was no Heaven for these lovely people, for they described the afterlife as the House of Darkness, the Yet, there were certain souls that were so corrupt, that they would not even enter the Underworld. These are the souls that would become a roaming phantom, bringing torment and death to their seat of the god Irkalla, the House from which none that enter come forth again.
Today the Ekimmu is believed to be found among the homeless, living in steam tunnels, sewers, and abandoned buildings in decayed inner cities.
The Ekimmu has rarely been labeled as vampire, but it reminds the Utukku (also known as Uruku) meaning vampire, who preys upon men.