Pearls are bound to the account you buy them with!

So you have to buy them with your real game account, or else you cant use them!

Just to clarify, you can have one account on multiple regions but the amount of pearls used to purchase items will differ for each region. This is where A-Coins come in, you can buy pearls for the region you are playing in and can exchange them on a per-region basis. This is to deal with local economies of different regions. You cannot transfer pearls from one region to another. Meaning, once the A-coins have been converted to pearls for a region, you cannot use them for another. ie: If you buy pearls for the korean server, you won't be able to use them in north america.