Hermione narrowed her eyes at the exchange and felt the warmth of Draco's presence beside her. "I don't trust them," he told her simply, low enough for only her to hear. "Especially Potter," he added, nodding to him walking away with Theo, trailed by a sulky Marcus – who was most likely disappointed that there hadn't been a chance to throw a fist – "Keep an eye on him for me, Penny."