"Very nice, Mr Zabini, Mr Malfoy!" Slughorn chortles, and Draco comes back to the present with a jerk. Zabini is handing in two vials of potion, casually bringing Draco's along with his own. Draco hadn't finished his, though, and he rolls his jaw at the knowledge that Blaise must have done it for him. Now he owes Zabini a favour, for fuck's sake. Fucking Slytherins; it's what he would do. He wonders what Blaise is going to want in return and groans internally. He can't leave himself open like that.