Beware the nice ones

Fred and George were lauded as being top of their class in early years and despite blowing off their OWL's are still lauded as genius's. After all, you can't invent if you don't have half a brain, right? But what would have if someone ever got these two jokers angry? I mean, really, REALLY angry? A 1 shot short, for your pleasure; beware the ones who laughs...