Ending - How to unlock
Ending #1 ("Bad") - Take too long during the final boss sequence.
Ending #2 ("Normal") - Hear no whistles in the Farplane during Chapter 3, and complete the game with any level of completion.
Ending #3 ("Sad") - Get four whistles in the Farplane during Chapter 3 AND have a file completion of under 75%.
Ending #4 ("Happy") - Get four whistles in the Farplane during Chapter 3 AND have a file completion of 75% or higher, but not 100%.
Ending #5 ("True") - Get four whistles in the Farplane during Chapter 3 AND have a file completion of 100%.