Aeshma (Aēšma) is the Younger Avestan name of Zoroastrianism's demon of "wrath", with his wrath being mainly directed towards the cow. As a hypostatic entity, Aeshma is the personification of violence, with himself being the lover of war and conflict. Along with the demon of death, Asto Vidatu, he chases the souls of the dead when they rise towards heaven. His standard epithet is "of the bloody mace", with his eternal enemy being Sraosha.
The name Aeshma, or Aeshma-daeva, would later be turned by Christian writers into Asmodeus, a demon lord representing lust.
Aeshmas appear in the Caracol and the Scorpio/Aquarius/Taurus/Leo Temples as common enemies, and later reappear in the Control Room of the Abandoned Factory. A conversation with Armaiti reveals that his female appearance is merely a disguise.