Ah, and while thinking about what they could be talking about, I remembered the onion soup I just ate, and when I tried to think about a monster that could be like an onion, I could just think about ogres... (because, as you might remember, they have layers. Like an onion)

But, since an ogre like Shrek would be a demihuman, I imagined the monster in question as a kind of swamp golem or something...