When playing Ni no Kuni it would be a good idea to be wary of a certain section of the game which could cause your save file to be destroyed as some press members have found.
Very early on in the game the player will receive a wand quest that should be treated with caution. Saving or restoring at the start of this quest will cause your save to be destroyed and you will need to start over. Luckily since it happens within the first hour the damage shouldn’t be cause too much frustration, however hopefully the bug will be fixed soon.
Best to keep this in mind when the game launches.