Dr. Who was created by a teenage human male called Jason who used to be the Master of the Land of Fiction. Just as the Doctor had various incarnations, so did Dr. Who, changing as the Doctor himself regenerated. Dr. Who inhabited a more simplistic and less morally ambiguous life than the actual Doctor. The Seventh Doctor encountered him in the Land of Fiction whilst travelling with Ace and Bernice Summerfield, (PROSE: Conundrum) and would again come into conflict with him in the real universe. (PROSE: Head Games)
Behind the scenes
The character of Dr. Who first appeared in the Virgin New Adventures novel Conundrum as a way to meta-textually comment on the difference between the Doctor as seen in the Doctor Who television series with the version seen in early comics and the version of the character seen in the Doctor Who Annuals, who, at times, behaved very differently from the television Doctor.