Here is the full list of all 20 Boo! Greedy Kid achievements.
Finish all levels
Get tased
Finish two third of the main campaign
Get one third of all the stars
Shout on 200 persons
Get caught by a robot-cop
Shout on a SWAT
Finish one third of the main campaign
Slam a door in the face of someone
Dodge roll 100 times
Taunt someone with your butt
Slam a door by rolling through it
KO a nurse
Finish a level with just one hearth remaining
Finish your first level
Shout on your first victim
Get two third of all the stars
Get all stars
Hide behind a furtinure 100 times
Earn $5000