Any pretence of holding her temper back exploded and Pansy cast the Revulsion jinx followed quickly by the jelly-brain.
Nobody spoke to her like that; she could handle (barely)the insult about Draco but the mention of her family and the comment about her looks was too much for her.
"You wouldn't what the pinncacle of anything was. You've never been worth anything Capper and you never will be."
Confident that her spell would have worked, she turned to head back to the Dorms and systematically tear and break things into smithereens. It was the most sensible alternative to re-arranging Cappers face.