Unlock Characters
Len - Watch "Servant of Evil".
Luka - Watch "No Logic".
Rin - Watch "Daughter of Evil".
Meiko and Katio - Watch "On the rocks".
Unlock Costumes
Snow Miku Costume - Buy 10 costumes for Miku.
Mikurisutaru Costume - Get SS Rank (Perfect) in a song (any difficulty).
Any other Costume - Select the song PV mode that is related to the Character. Watch it until the end menu appear.
Unlock Misc. Bonuses
New Room Designs - Idle in the room screen for a few hours.
Use Mii in AR Live Mode - Buy all costumes.
Sound Effect Type 3 and 4 - Get SP ALL in all song (any difficulty).