You can make him go away by talking to him. There's a chance you'd trigger the dialogue where you can ask him to leave. And no, he isn't an evil doll, he's the special doll. In the premium version you can keep him along with the other dolls :)
Awww ;-: Thanks for your help, is it ok if I take screenshots of him? Or any of the other dolls?
Of course :3 Feel free to.