The Yule Ball ran late enough that no one was checking corridors too closely, and Kevin and Hermione took full advantage of the extended curfew before eventually making their way back.
Their route through the quieter parts of the castle brought them around a corner and directly toward two figures at the far end of a dimly lit passage — Professor Snape, and Karkaroff.
Karkaroff was pulling his sleeve up. He was showing Snape his forearm, speaking in a low, urgent voice, and even from this distance the mark on his skin was moving — not a tattoo, something alive, shifting against the skin.
Kevin clocked the Dark Mark in one glance and kept his expression neutral.
Snape's face was blank, giving nothing. His posture said he was listening and would continue to listen for as long as required and would give back nothing.
Karkaroff noticed the two of them down the corridor. He yanked his sleeve down fast and stepped back.
Snape turned. He looked at Kevin and Hermione walking toward him, hand in hand, at this hour.
"The curfew extension applies to the ball," he said. "Not to unsupervised wandering."
"What unsupervised wandering? We're clearly here." Kevin glanced around. "With a professor."
Snape's jaw tightened. "Ten points from Gryffindor, Mr. Kevin."
"Understood."
Hermione grabbed Kevin's hand and walked. Quickly.
In the corridor after, she pinched him. Hard. "He didn't dock us for being out late together, and you made him dock us for something else entirely."
"He was going to dock us anyway. At least this way I got a line in."
"He has been unusually decent to us lately. You keep pushing him and he's going to stop."
"We have a different kind of relationship, Snape and I. It transcends normal student-teacher—"
"He is going to destroy you."
"He won't. We understand each other."
Hermione made a sound of pure exasperation and walked faster. He kept up easily, still holding her hand.
Back in the common room, the Gryffindors were still up and immediately began cheering at the sight of them.
Hermione, who had spent years determinedly not being the centre of attention, turned red and fled upstairs at a near-run.
Kevin ducked into the boys' side and changed, emerging to find Harry and Ron already in pyjamas, apparently waiting.
"Where did you two disappear to after the first dance?" Harry asked. "We lost you completely."
Kevin picked up his book from the nightstand. "Privacy exists, Harry."
Ron muttered, "I knew it. The second the dancing finished, gone."
"Ron," Kevin said pleasantly, "do you want me to bring up the topic of Draco and Astoria?"
Ron's face did something complicated. Harry interjected immediately. "Don't — he's only just calmed down from the last — Ron, tell Kevin about what Draco said at the ball—"
Ron's expression shifted to something much more animated. Draco had apparently been forthcoming at the ball — two glasses of punch and several hours with no romantic option of his own had made him unusually candid about Astoria Greengrass. Her hair. Her opinion on the Triwizard Tournament. The way she'd laughed at something he'd said without being polite about it.
Kevin listened with genuine interest.
He knew, in broad strokes, how Draco Malfoy's life went in the version of events he'd arrived knowing. He was glad it was going differently.
Harry woke in the dark, soaked in cold sweat.
The graveyard again. The statue of Death, stone scythe raised. The same figures.
He lay in the dark until his breathing steadied. Then he sat up and started thinking about the second task.
Three days later, they were at the Black Lake. The surface had re-frozen after the chaos of Kevin's arena demonstration, a sheet of grey ice over dark water.
"Bubble-Head Charm," Kevin said, when Harry asked about breathing underwater. "Or gillyweed. Both work. Charm is more reliable over time — gillyweed duration can be variable if the batch is old or wasn't stored properly."
"And the Bubble-Head Charm is safe?" Hermione looked up from her book — A Study of Highland Lake Creatures, Kevin had noticed her carrying it for a week.
"If cast correctly. If the bubble's seal isn't complete, you run out of breathable air without any warning. But that's true of every charm — get it right and it's fine."
"And if Harry can't get it right?" Ron asked.
"I've got some gillyweed stored. Good quality, recent batch. But his priority should be mastering the charm."
Harry nodded, filing it away. A month was workable.
"What about you?" Ron asked Kevin.
Kevin raised his wand and aimed at the lake ice. It cracked with a sound like a rifle shot. Water surged upward in a column twelve feet high — and then, with a second motion, it twisted. The column folded and curved, took on shape, and for a moment above the Black Lake a water dragon coiled, thirty feet long, crystalline and roaring, before he released it and it fell back as rain.
Where the ice had cracked there was now a clear corridor of open water going straight down — the lake visible all the way to the bottom, held open by a pressure boundary of contained air.
Harry and Ron stared at it for about five seconds.
"Teach us that," they said, simultaneously.
"Master Hephaestus's Command first." Kevin crouched and looked down through the open water. "That's the prerequisite."
Harry had been working on Fireball for two months. Ron was still on Smoke Burst. Both of them slumped.
Hermione, who had been watching this from the bank, had at least the decency to look only moderately smug about having got further than either of them.
Harry sighed and settled in for another afternoon of Bubble-Head Charm drills. At least Ron was doing them with him. Shared suffering was something.