Part of the charm of Fat Princess is how bloody drenched violence is contrasted with cute characters and cake. That charm, it seems, does not translate to the Japanese market.
The game, retitled Pocchari Princess ("Cubby Princess") for The Land of the Rising Sun, is getting a domestic Japanese release on the PSN and the PSP later this November. The trailer Sony is running on the title's official site is entirely blood-free. Pocchari Princess does carry a warning about violence — but, the actually blood letting appears to be censored as it often is for Japanese titles.
We are following up with Sony Computer Entertainment.
ぽっちゃり☆プリンセス [Official Site Thanks, Neer'mo!]