Here is the full list of all 8 Bombing!! 2: A Graffiti Paradise achievements.
Unlocked the Paint Roller
Unlocked the Paint Pen
Unlocked the Radio
Unlocked the Wheatpaste Brush
Unlocked the Lantern
Sprayed in Graffiti Paradise for 2 hours.
Spray in Graffiti Paradise for 5 hours.
Unlock Rappeling