Credits to Pwnthis

Tools (download these tools in Download section):

1 fiddler2
2 firefox/chrome/ie
3 Pink Throne 2109 Database  link 1 | mirror 1 | mirror 2

Steps:

a. Download the files above.
b. Using fiddler, replace database.dat and ShopMystery2108.dat
c. Clear Cache and reload Pet Society.
d. If replaced correctly, you will see the new items in the shopmystery.
e. For coins cheat, go to Mystery Shop, click on the pink throne and it will ask if you want to purchase a win or lose box at 150coins. Return home and open those boxes and the Pink Thrones will appear which you can sell for 999coins each.