So the thing in that weird painting seems like a creature of some sort. I'm seeing a blue body on tentacles, looking more like tree roots than traditional tentacles. On the left side appears to be a tentacle arm. The head appears to go up and down, like a faucet, and on the face is a golden mirror encrusted with jewels. I would imagine it to be more of a monster than a passive creature that causes people to go insane in their reflections.