Supposedly a leader of the fallen angels, Semyaza was also known as Shemhazi or Shemayza. One of the "Sons of God" who cohabits with women. According to lore, Semyaza cohabited with one of Eve's daughters and produced two sons who ate every day one thousand each of camels, horses and oxen.

As punishment for his sins, he hangs upside down in the constellation Orion, suspended between heaven and earth.
source for additional reading/information:

Davidson, Gustav. A Dictionary of Angels. New York: The Free Press, 1967.