i wasnt super excited about this game. Since I cant read Any Japanese (Except for the items) I wanted to buy the game so that I know the story. Its just such a pain that I have to play through the game twice just so that I can use the new hi ougi's.
Well, for the American version, once you beat the game you can save your clear data onto a different file (or you could overwrite your original file if you don't care about it anymore, but it's recommended that you don't) and continue it. It will let you access the grade shop once you continue it and you will still be at the end of the game, but now you can go back to previous areas and do things that you originally could only do during the 2nd playthrough in the Japanese version.