A comics style picture of Jack Black against a background of flames and smoke. He is wearing a Bowsette costume in the goth style, including horns, black nail polish, tight fitting shoulderless dress, and a pink crown. His hand is raised in a casual "Love you" hand signal, and he is sporting a triumphant/rebellious expression.
Fair question. I got it from a private forum I belong to. I'll look around for the official source.