Well, I mean, isn't that kind of Cerberus in the first place if he didn't have a job in the Underworld? Oh, I do know the game Hades. I bet they'd be awesome CR, being sons of Hades and the life they had. Nico with Thanatos or the Furies would be fun too.

Ah, working together to survive - a concept Nico is familiar with. He's a stubborn kid, so a long struggle is not a deterrent.