Unlock alternate ending and two more costumes:
Complete the game under Nightmare difficulty.
Unlock Feel and Expand camera abilities:
Complete the game under Easy or Nomal difficulty.
Unlock Hard Mode, two alternate costumes, and Mio's glasses:
Complete the game under Normal difficulty.
Unlock Maid costume for Mayu:
Complete all missions in Mission Mode.
Unlock Mission Mode, Gallery, Ghost List options:
Complete the game under Easy or Normal difficulty.
Unlock Set-Up Information:
Complete the Ghost List.
Unlock two alternate costumes:
Complete all missions in Mission Mode with a "S" ranking.
View the alternate ending, unlock Nightmare mode, Album mode, true ending sequence, and two more costumes:
Complete the game under Hard difficulty.
View the first ending:
Complete the game under Easy or Normal difficulty.