She could see the confusion and it struck her, plucked fragile heartstrings gently. Her lower lip bitten. She paused when he stepped back, then waited for a moment.
Gently she reached to touch the cat's head, brushing her fingertips over a cooling ear. There's no grabbiness, no intent to take it away, nothing fast or startling in the way she moves.
"It's mortal Deimos. When mortals die, they don't come back." The usually left out, of course there had been exceptions. Necromancy, and a few deals with Hades that she knew about. Those didn't matter at the moment. "It's just.. a body."
A deep breath taken. "You may keep him, for a little while, but eventually, he will fall apart." Her hand fell away from the cat, then smoothed against the stubborn, petulant cheek of the boygod.
"If you want to keep mortal pets alive, you cannot hold them by the head like you were. You cannot squeeze too hard. You must feed them, water them, keep them warm but not too hot. Mortals are fragile."