Daeva

"A Daeva. It translates to "Demon of Darkness" -- Zoroastrian Demons, they're savage, animalistic and have nasty attitudes -- kinda like Demonic pit bulls. These Daevas, they have to be summoned. Conjured. These suckers tend to bite that hand that feeds them....and the arm and the torso." - David Remington.
A Daeva is an ancient demonic creature of shadow, a special type of Demon that can be summoned by other Demons . Similar to Hellhounds and unlike most Demons, these Demons don't need a host to attack humans. Also, like Hellhounds, Daevas are beings used by Demons as invisible killers. While they are visible, they appear as humanoid shadows. They are known to turn on those who controlled them once that control is lost.