The teenagers had just finished mixing a strange concoction between them and rid themselves of their shirts. When Harry looked up, he first met his eyes and then glanced towards Voldemort and Barty. An unspoken exchange took place before the Dark Lord nodded rather insistent. With a sigh, the teenager decreed, "Severus Snape, you will not do anything to disturb, interrupt or otherwise impede this ritual. Tell me you understand my order."