Nycaloth
Also known as nycadaemons, nycademons, and sky demons, these fiends are the elite air cavalry in yugoloth armies, swooping down onto enemy flanks and tearing up unsuspecting troops.
They are the lowest of the greater yugoloths and bitterly resent it, constantly scheming to ascend to greater status and prestige. They sometimes do so by binding themselves to the service of powerful humanoid spellcasters, serving as guards and killers, hoping the mages would grant them a portion of their power eventually.