Instigate
If you have spiders in your mouth, then you're going to instigate fights between people. Mostly because the spider in your mouth makes you grumpy, but also because the spider keeps telling you to be an instigator with its little mouth inside your own mouth.
Imagine having a spider in your mouth. Imagine being angry about it and instigating fights between people because of it.
さ
そそのか, そそ
None
The spider in your mouth tells you to instigate a fight by sawing (さ) the other person's leg off. It even whispers where you can find a nice big saw.
Picture the fight you and the spider instigated. The guy pointing at the saw, then pointing at his sawed off leg. Listen as the spider tells you to shake your head.