When something is just awesome or just conveniently works out the way you wanted it to.
SK: Wait, how are we getting to the rave?

Dave: On my llama you fool!

SK: Oh she's a per!! :)

(Upon receiving your McDonald's meal and being completely satisfied with it)

She's a per!!

Dave: When do we have to be home?

SK: We still have four hours!!

Dave: She's a per!
by Dave&SK July 6, 2011
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