Reccuring Dreams

During my childhood days, there used to a be character called "Kosh" in my dreams. It was strange how this got materialised in my mind during dreams (I never heard of this name in reality). Kosh used to scare the wits out of me whenever it came in my dreams. It used to periodically come in my dreams, appearing exactly the same way, (I don't quite remember now, the memory has become hazy). Mostly it used to hide below our cot, and I would accidentally trip down from the cot only to find it face to face.. and I would wake up to reality.
I wish to form a proper story with this character as the antagonist and try writing a horror story on the lines of my favourite RR Stein's Goose Bumps.