Ok, here's a weird one. Do you think it's feasible to be able to have pets like a cat, fish, or hamster, in an underground complex? Specifically it's an underground research facility that is a self contained city. There's a residential disctric, a shopping district, the lab, and other levels- and I need to know if you think certain pets could be kept down there. It isn't closed off to the world, so it's not like they can't dispose of the excrement or the dead bodies. This is for a novel I'm working on, and Google isn't helping. Apparently this isn't a topic on many people's minds. So question is, would you as a reader (for those who would be interested in the underground city plot) freely accept the presence of these animals underground? Could it easily be explained through narrative without sounding cheaply tacked-on? Specifically need an answer on the cat, please. Thank you!