[Muffet tilts her head thoughtfully, giving the idea due consideration.]

Hmmm, that does sound plausible. I know there are a number of plants with magical properties that only grow underneath Mt. Ebott, like the echo flowers. Perhaps something about us gives them what they need to grow properly?

[Maybe monsters are to magic what bees are to pollen??]

And humans certainly do seem to have natural strengths in many areas that monsters lack, and vice versa- a sort of balance. It wouldn't surprise me if we made up for each other's weaknesses quite well, working together.