In America the main character sprite is wearing pants in the US version but in the Japanese version he is wearing a ceremonial dress.
Interestingly enough, both sprites were programmed into the American cartridge so if you put in a Japanese system the character would have the ceremonial dress and if you put the same cart in the American system he would have pants and short hair.
In the original release of this game there was nudity at the end. When you save the princess she is stark naked. This was discovered by angry parents and SEGA made a second version with exactly the same package in which the princess at the end of the game is wearing clothes.
It's famous for being an early example of nudity in video games.