Silverrose

The Betrayer (also called Silverrose, typically only by their followers) is called the prince of puppetry and madness. Their namesake comes from an ancient crime they committed against the other princes. They have been worshipped as one of Mesnea's demon princes for all of recent memory.

Their symbols are usually associated with red roses and thorns.

If manifested, they're said to have a forked tongue, to wrap themself in thorny vines, and to leave any who see them mad, comatose, or otherwise influenced in unknowable ways.