CONVERSATION! Megan tried to adopt a laid back, 'cool' expression. It may have been overacted. "Oh, just about everyone, I think. Well, I don't know about a lot of the Ravens or Slytherins. I'm assuming everyone will at least show up though. Wayne Hopkins, the Hufflepuff captain, was telling everyone in our common room they had better get themselves to the Quidditch pitch earliest to get the most from the workshop." She imitated Wayne's loud and demanding voice.
Oliver most likely would know Hopkins at least by his last name. He was certainly one of the more rambunctious young Quidditch players when Oliver was a 7th year.