Complete the game and save after the credits. Then load the cleared saved game file to start a New Game+ playthrough which allows access to the Grade Shop where you can purchase the following items for the indicated amount of Grade. Any leftover Grade will be kept for your next playthrough.
1/2 Experience: 10 Grade
10x Experience: 3,000 Grade
2x Experience: 1,000 Grade
2x Gald: 600 Grade
Decrease Starting HP by 150: 10 Grade
Display Synopsis from Beginning: 10 Grade
Double Grade increase and Decrease: 100 Grade
Increase Max Item Limit to 20: 400 Grade
Increase Over Limit fill speed: 450 Grade
Increase Starting HP by 500: 250 Grade
Inherit AD Skills: 900 Grade
Inherit Artes Learned: 1,000 Grade
Inherit Artes Usage: 100 Grade
Inherit Battle Info: 10 Grade
Inherit Capacity Cores: 500 Grade
Inherit Character Disc Info: 10 Grade
Inherit Collector's Book Data: 10 Grade
Inherit Cooking Ability: 50 Grade
Inherit FS Chambers: 150 Grade
Inherit Gald: 1,000 Grade
Inherit Items: 500 Grade
Inherit Mini-Game Data: 10 Grade
Inherit Recipes: 50 Grade
Inherit Special Items: 10 Grade
Inherit Titles (Including Costumes): 500 Grade
Inherit World Map Info: 10 Grade
Inrease Combo Bonus: 50 Grade
Play Time Carried Over: 10 Grade