You and Pansy didn't like each other very much, she bothered you too much and made very offensive comments towards you, and of course you defended yourself as best you could.

one day you were in the halls but you were being bothered by other students, Pansy saw that and pushed the student who was bothering you very hard

"The only one who can bother him is me and if you bother him again it will be much worse for you"

she said annoyed as the student got up and ran away