That little step closer puts James in Scorpius's personal bubble. And Merlin does he hate when people bully him like this.

"Name one thing you know about me besides my last name," he spits coldly. "How in bloody hell would you know we've got nothing in common if you don't even know me? Now, step aside, or I'll make you step aside." Look at that, it's even got Scorpius flustered enough to be a little red himself.