"Please wash it off, I don't like the dwellings of my brother anywhere near you." Poseidon was more than a jealous and possessive lover, and sometimes he could put his foot down on where she went. Hades was not allowed to keep his stench on her any longer. He'd been in that dungeon before and it was torture, more than torture, it was like he wasn't able to breathe. They were both made for the open water, not the caves of the Underworld.