All the demons in Supernatural, when they exit their human vessels, are in form of a black smoke cloud.
However, in Season 9 Episode 10, Crowley enters into Sam's body to ask him to expel the Gadreel. Here he is seen moving from his current body to Sam's body in form of a red color cloud. Why is his color different from other demons?
What's different about him, even strong demons like Abadon are in black cloud form?