Throw away for obvious reasons.
When I was a child I had an "imaginary" friend yet he was extremely real to me. This went on for years and helped me with a lot of stuff in my life. I'd always hear I was "mature for my age" and I attributed it to my imaginary friend who helped me understand things I didn't really understand.
I wouldn't always see him most of the times I'd just hear him. He had no name whatsoever, at least I never asked and he never told me.
This could just be your regular "imaginary friend from a creative mind" situation -- the paranormal part is he would tell me things I wouldn't ordinarily know. People would always call me lucky yet those small moments of fortune were results of me doing things he told me to do and I knew, because of him, the exact outcome.
He was a "good guy greg". I feel I learned to be a good person because of it.
When I was around 13-14 years old I started hearing a second voice, never saw it, and it would tell me things which weren't so nice. Voice #1 and #2 started arguing. I remember it clearly, one day in my bed I couldn't stand the fighting anymore, it was like people shouting and I said "enough, I don't want to hear either ever again, leave me to my own decisions".
That was it, I never heard either anymore.
FIY I'm a perfectly normal adult, no mental or health issues, successful education, career and relationship.
EDIT: Wow, I never expected this to attract so much attention. I'll try to reply as much as I can.