A childhood belief about imaginary friends

At this time I've an imaginary friend, who, really, isn't very 'friendly'. He is a clown - like evil spirit with red puffy hair, blue eyes and super pale skin. He often never wears clothing, except a wrapping of cloth below his abdomen and around his buttocks. He looks as if he has absolutely no fat on his body whatsoever. My usual way of communicating with him is either through my thoughts or by singing or playing the piano. He is hardly ever really kind to me, and often puts me down about things. But whenever I ask him to help me or encourage me to do something, he is more than happy to oblige. He follows me everywhere I go, usually appearing behind my shoulder, whispering things in my ear. I've yet to know his name.