"We can prank everyone." Harry told him, "If you spread out who you prank it makes it harder for people to figure out who the prankster is." Harry was curious as to why Faustus seemed intent on the Gryffindors but wasn't sure if he should ask in front of Severus. From the look on his face he wasn't sure Faustus would answer right now. Better to ask later.
"Though we probably shouldn't prank the professors. I think the school has some that would still put graduates and those not enrolled in detention." Like Severus.