The overlooked, second female Smurf
(yes, there was more than one, fucker.).
Sassette was created by the other Smurflings (Nat, Snappy, and Slouchy) to keep them and Smurfette company. Unlike Smurfette, was much younger and a tomboy. Of course, when you and Smurfette are the only females in an predominantly all-male village, you have to stick together.
Sassette told Brainy to smurf off.