Physiology
BadBoyHalo is a humanoid demon with white eyes. His face is shadowed by his hood. He wears a black and red robe, with black and red pants and gray shoes. Strapped to his back is a diamond sword. He has canonically confirmed that he is 9'6 feet tall.

After the Egg completely took over Bad's body, the red accents from his clothes were replaced by white accents, as if the red was sucked out of him.

According to Puffy, his nose wiggles when he lies, though he has denied this. 