From behind her Sirius yelled,
"Petrifacus Totalus!" and Raven fell to the floor, her arms and legs stuck by her sides. James pointed his wand at her and said something under his breath. She flew up to the ceiling and was stuck to it as if by glue, facing downward so she could see what was going on. Her back was stuck to the wall. James picked up her wand and pocketed it, before turning to Snape again. Sirius had also turned and said with a laugh,
"What's this? Snivellous has got some friends to stand up for him? Ah well, 2 on 1 on James, now it's 2 on 1 on you."
"Silencio!" James silenced Raven and then said to her,
"It was three on one before, don't you remember?" Then he turned back to Snape, "Anyway, I wouldn't want you so publicly embarassed. You versus me, with no spectators. I'll bring Sirius as my second and you can either of these two. And one referee on each side. Say the two nights from now by the whomping willow?"