So as luck would have it, I found the Japanese soundtrack for Beauty and the Beast, movie edition in the 500 yen bin. And the lyrics... are entirely different from the musical soundtrack.
So, for completeness, Gaston, the movie version.
( Full of transliterated goodness )The movie version is a more literal translation of the English lyrics. But the flow of the song is a bit awkward in several places. I think they did a new translation for the musical because that version flows a lot better, even if it's no longer so close to the English (ie the line where Gaston sings about his chest hair is literally translated in the movie lyrics, but in the musical lyrics he simply expounds on the perfection of his body.)
But at least the movie lyrics include the talkie bit at the top of the song.
And now we can have both version in the DB. And you can choose which one you want to sing. :D