The brother of Asmodeus, it is said the he created the first mortal, by discovering the concept of souls and worship.
He and his brother got into a fight over whether or not mortals should have free will. When they met on the battlefield, Asmodeus offered his brother his hand in friendship. Ihys, being some sort of cosmic idiot, accepted, and was promptly murdered by Asmodeus in the first act of treachery. Which isn't very Lawful of Asmodeus.
For some reason, Asmodeus was sad that he murdered his brother, and allowed mortals to keep their free will. Which does raise the question of why Asmodeus went through the effort of murdering his brother to prevent free will.
As the first creature to die, Ihys became the first soul to be judged by Pharasma.