Unlock new game mode
Complete the game.

Hard Mode
Beat Normal Mode.

Bonuses
Clear game bonuses:
Unlockable: How to Unlock:
Additional scene Collect all secret reports.
Another Day Beat the game once.
Chapter Selection Beat the game once.

Secret Ending Scene
Collect all secret reports.

Chapter Select
Beat the game once and you'll have the option to go to any chapter in the game and play it again with bonus objectives.

Another Day
After beating the game, this chapter will be added in the chapter selection menu. This chapter is unrelated to the main story/plot.

Save Screen Sprites
After completing various tasks, you will unlock different character sprites on the save screen. You start off with Neku at first.

Unlockable: How to Unlock:
Beat Complete the third week
Joshua Complete the second week
Mr. Hanekoma Collect all secret reports
Rhyme Collect all items
Rhyme (noise form) Complete the noise list
Shiki Complete the first week

Easy PP
Enter a battle with those Jellyfish noises. Kill the other non-jelly enemies and leave the Jellyfish. These guys will tend to multiply if left alone. They still count as individual enemies so you'll have more pins and PP if you defeat all of them.

Easy money and PP
You earn massive amounts of Yen pins and PP if you chain battles. Additionally, the higher your difficulty and the lower your level the more loot you'll get.

Damage bonus
Shibuya is all about trends. If you equip accessories and clothes from a specific brand, chances are it will top off the charts. Same thing with pins. If you use pins when battling noises in the same area, its brand will increase and you'll enjoy a nifty damage bonus.

Display total gameplay hours
Hold L + R on the save data menu screen to see your total gameplay hours.