Felix was trying to conceal his incredulity. Remus had spent most of their friendship enduring Felix's flirting with gentle humor while quietly, but decidedly, deflecting him. Now Remus was speaking to him like an ill-behaved bottom who hadn't earned the firm handling he desired. The change seemed quite sudden to Felix, but it looked so natural on Remus that he was beginning to doubt all his previous assumptions.

And when Remus looked at him like that, clucked at him like he was in a fit of pique, Felix rather wanted to press him back against the wall and show him just how badly he could behave. His eyes widened in a quick flare of surprise, before narrowing down again, calculating.

"Do you think you could?" he lilted, leaning a fraction of an inch nearer, as though Remus had a secret to tell him. Felix lowered his voice. "I should be delighted to volunteer, if Sirius grows too excitable to manage." His own small smile and steady gaze said clearly that if Remus wanted to play with him, Felix was ready to call his bluff.