"Are you aware of the time, Potter?"
James ruffles his hair, the picture of calm except for the tightening of his grip on his Nimbus. "Professor! I am not aware of the exact time - you know how it flies by when you're er- flying."
McGonagall's lips tighten, probably more to suppress a laugh than out of actual anger. Though her tone seems to have no trouble keeping that determination firmly in the 'detention is imminent' zone. "It's well past curfew."
"I - "
"And you are Head Boy."
"Yes," James says in his silkiest tone, trying to recall all he's learned from Remus's slippery ways over the years, "But I am also Quidditch Captain and I was trying out some new plays - "
"By yourself?" McGonagall asks, brow raised, "Hardly seems productive."
"I was mostly envisioning it on the field. All that space makes it come alive. Have to write it down."
"And your notes are where?"
When James ruffles his hair this time, he grips the roots for a moment, knuckles going white. "In my locker. Nice and secure," he winks, "Gotta keep things hidden so Hufflepuff doesn't get any ideas."
"Because they are known cheats," McGonagall replies, dry.
Almost as dry as James's mouth. This may never end. He's half convinced giving himself up is a better idea. But then he remembers why the whole charade started in the first place. "Competition makes liars of the most unexpected people, Professor," James says sagely.
"Potter!"
James and McGonagall both jolt at Lily's somewhat shrill yelp. "I have been waiting in the common room for forty-five minutes! We have schedules to complete and you're supposed to do your half of the star chart before tomorrow night," she turns toward Professor McGonagall, "I am terribly sorry for the outburst."
Her eyes wrinkle at the corners as she examines James and Lily for a few beats, then sighs. "Off you go - straight back to the Common Room with no stops in between."
James's breath blows out in a long gust. "Aye, right away!"
They're almost to the stairs when McGonagall calls out, "And Evans, Potter, scarves are particularly useful on nights like these. Against the…chill."
She stares pointedly at their necks enough that both reach up, remembering the actual happenings on the pitch.
"Get on, now," McGonagall says, shooing them with one hand, "I would like to get some sleep."
They're a few floors up, waiting for the moving staircase when James turns to LIly, "Did Professor McGonagall just give us snogging advice?"