I've had problems with my PSP, so I'm posting from an internet cafe.
This was supposed to be an easy one, but since it hasn't turned out that way, here are some big hints:
It is a japanese HuCard that was not released for TurboGrafx-16.
It is a game that is not exclusive to PC Engine.
It did not originate on PC Engine.
That sprite is not burried deep within the game and it can be found very quickly.