In ghost form you have both your allies and enemies' status info to hand, and are able to strengthen party members and weaken enemies via the Vita's touchscreen. You're a bit like your party's guiding spirit, except presumably covered in a white blanket with eye holes cut out. Either way, it sounds like an intriguing way to keep players involved after death.
Inafune also went into the lore of a Soul Sacrifice monster called Leviathan, the beastie pictured above. Apparently Leviathan's origins relate to a tormented prince, and his wish to claim the throne by having his twin brother killed by a tortured pet crocodile. This is just one of the reasons we advise caution in choosing a crocodile for a pet.
Soul Sacrifice hits Japan on March 7, 2013. North American and European releases are confirmed, but publisher Sony Computer Entertainment hasn't disclosed their timeframes.