1.) TV Tropes is a wiki, so if it doesn't have something you can always add it. For instance, I was sad that Wizard People, Dear Reader didn't have a page, so I made one myself. You can do the same thing here. In fact, it'd actually be awesome if you did.
2.) Part of the fun of WMG is that the guesses are usually possible
. I really doubt a dog and a cat will be procreating.