The lesson, mercifully, was about algebra.

Leo had never in his life been so grateful for the existence of quadratic equations. Algebra was the same in every world, apparently - the same impassive symbols, the same teacher's voice working steadily through them, the same comforting sense that none of it had any opinion about him whatsoever. For the first time since he'd walked through the school gate, Leo felt the tight knot under his ribs begin, slowly, to loosen.

This was what he wanted. This was the plan. A desk, a notebook, a problem on the board, and the blessed anonymity of being one student among thirty, no one's eyes on him, nothing required of him but to copy down numbers and be quietly forgotten.

He copied down numbers. He was quietly forgotten. It was wonderful.

Well - mostly forgotten. Every so often he was aware of a head turning somewhere behind him, a whisper passing along a row, the prickle of attention landing on the back of his neck and then guiltily retreating when he didn't react. But it was manageable. It was background. He could survive background. He bent over his notebook and made himself as boring as humanly possible, and slowly the room seemed to accept that the new boy was not going to do anything else thrilling for the moment, and turned its collective attention back to the front.

The one exception sat directly to his left.

Leo became aware of Scarlett Vance the way you become aware of a particularly upright tree - not because it does anything, but because of how completely still and certain it is. She didn't fidget. She didn't whisper. She sat with her spine straight and her attention fixed on the board, and she took notes.

And that was the thing Leo's eyes kept snagging on, though he couldn't have said why. The way she took notes.

It wasn't normal note-taking. It was something closer to architecture. Her handwriting was small and precise and ferociously neat, the lines ruler-straight even though she wasn't using a ruler, the margins exact. She had three different colored pens lined up at the top of her desk in a tidy row, and she used them in some private system he couldn't decode - blue for most things, red for something, green for something else - switching between them with a brisk economy of motion that suggested she'd done it ten thousand times. There was a small stack of folders beside her notebook, none of them to do with algebra, edges squared off against the corner of the desk. While the rest of the class did one thing - listened to the lesson - Scarlett Vance appeared to be doing the lesson and, simultaneously, several other invisible jobs, her pen darting between the maths and a list in the margin that Leo was fairly sure was a schedule of some kind.

She was, he thought, the most organized person he had ever sat next to. And underneath the organization, if he looked - and Leo always looked, it was a habit he couldn't switch off, noticing the small things other people walked past - there was something else. A tightness around her eyes. A faint, controlled urgency in the way she moved, like someone carrying a stack of plates across a crowded room and absolutely refusing to let it show on her face. She wasn't relaxed. She was performing relaxation, the way Leo himself performed invisibility, and he recognized the effort of it because he knew exactly what it cost.

She's tired, he thought, and was faintly surprised at himself for thinking it. She's doing too much and she's tired and she won't let anyone see.

He filed it away, the way he filed everything, and went back to his algebra. It was none of his business. He had five rules, and none of them was concern yourself with the inner life of the girl next to you.

The lesson rolled on. The teacher set the class a page of problems to work through, and the room settled into the particular rustling quiet of thirty people pretending to do maths. Leo worked through his problems steadily. Beside him, Scarlett worked through hers and, evidently, three other things at once, reaching at one point for a folder from her stack and flipping it open to check something against her notes, her pen tucked behind her ear, then in her hand, then tapping against her lip as she frowned at whatever the folder told her.

And then - it was such a small thing - she reached across to pull a second folder from the bottom of the stack, and her elbow caught the pen she'd set down on the edge of the desk, and it rolled.

It rolled off the edge, bounced once on the floor with a small plastic click, and came to rest against the leg of Leo's chair.

Leo looked at it. It was the red pen - the one she used for the important things, he'd noticed, the rare careful underlinings.

He picked it up.

There was no thought involved. There was no calculation, no awareness of context, no memory of last night's reading or the morning's disasters or the careful taxonomy of who-does-what-for-whom that governed this entire upside-down world. There was a pen on the floor and a person it belonged to eighteen inches away, and Leo's body did what Leo's body had always done, which was the small useful thing. He bent, retrieved the pen, gave it a reflexive wipe against his sleeve to clear the dust, and held it out to her, two-handed, with an easy, unthinking smile.

"Here," he said. "You dropped this."

Scarlett Vance looked at the pen.

Then she looked at Leo.

Then she looked at the pen again.

Leo had, by this point in his short tenure at Silverleaf, seen this exact sequence of looks several times - from the nurse, from the girl at the door, from a dozen people in the corridor. He'd come to think of it as the double-take, the small visible buffering that happened when he did something that to him was nothing and to them was apparently astonishing. But on those other faces it had come with the soft dazzled wonder, the pink cheeks, the leaning-in.

Scarlett's face did something different, and more interesting.

For one unguarded second, the entire architecture of her composure simply fell away. The cool assessing President vanished, and underneath was a girl who looked, frankly, ambushed - eyes a fraction too wide, lips parted on a word that didn't come, every ounce of that ferocious control caught flat-footed by a boy holding out a pen. It lasted no longer than a heartbeat. But Leo was a noticer, and he noticed it, and he filed it away with quiet bafflement next to the tiredness and the too-many-jobs: oh. She wasn't expecting that. Why wasn't she expecting that? It's just a pen.

Then the second passed, and Scarlett's composure came slamming back down like a portcullis.

"I -" she said, and stopped. Her voice had come out wrong - higher, less certain than the crisp authority he'd half-heard her use with the teacher. She seemed to hear it too, because she stopped, set her jaw, and tried again. "Thank you."

She took the pen. Her fingers were careful not to touch his, which Leo took for ordinary tidiness and which was, in fact, a small act of self-preservation. And as she took it he saw, with the helpless precision of someone who can't stop noticing things, the flush climb up the side of her neck and bloom across her ears - a deep, betraying red, entirely at odds with the stony set of her face. She was blushing furiously and fighting it with everything she had, and the fight was visibly, comprehensively losing.

Leo's first feeling was alarm.

Had he done it again? Some terrible breach of etiquette, some rule he hadn't read about, some way in which picking up a pen was, in this strange place, a deeply inappropriate thing to do? He ran back through it. He'd just - the pen had rolled - he'd handed it back - that was all -

"Sorry," he said quietly, because sorry was always a safe bet. "Did I - was that not okay? You just dropped it, so I -"

"It's fine," Scarlett said, far too quickly. She was looking very fixedly at her notebook now, the red pen gripped in her hand hard enough to whiten her knuckles. "It's - it was fine. It was nothing."

"Okay," Leo said, uncertain. "Good."

A silence stretched between them, taut as a wire. On Leo's side it was the anxious silence of someone braced for having committed a social crime. On Scarlett's side it was something else entirely, something he could feel radiating off her like heat off a road in summer but couldn't begin to interpret - a kind of furious, scrambling internal recalculation, the sound, if recalculation made a sound, of someone frantically trying to file a thing that didn't fit in any of her folders.

Because Scarlett Vance had spent her entire life being the one who picked things up.

She was the eldest Vance. She was the Student Council President. She was the one who managed the timetables and resolved the disputes and stayed late and carried the load and held the plates, all the plates, and never once - not once, in seventeen years - let anyone see the strain of it, because to be seen straining was to be seen as weak, and to be weak was, in the iron logic she'd built her whole self on, to be a burden. She did not get things picked up for her. She did the picking up. That was the arrangement. That was the deal she had with the world, and it had never, ever broken.

And a strange ordinary boy had just leaned down without being asked, without wanting anything, without even seeming to notice he was doing it, and picked something up. For her. Handed it back with a smile that asked for nothing in return, that didn't even know it was offering anything. Not because she was the President. Not because she was a Vance. Not out of fear of her authority or hope of her favor - he plainly had no idea she had any authority to fear or favor to hope for. He'd done it for no reason at all except that it had needed doing and she was a person standing nearby.

It had landed somewhere in her she didn't have a name for and didn't want to examine, somewhere far below the President and the eldest daughter and the manager of all the plates, and it had said, very quietly: someone could just do that. For you. And not need anything back.

Scarlett did not have a folder for that. So she did what she always did with things she couldn't file, which was to bury them under work and authority until they stopped making noise.

She cleared her throat. When she spoke again her voice had been hammered back into shape, crisp and cool and official, the President restored.

"You should focus on the lesson," she said, eyes on her notebook. "You're new. You'll have material to catch up on."

"Right. Yeah. Of course." Leo, relieved beyond measure that whatever crime he'd committed seemed to have been pardoned, bent obediently back over his algebra. "Sorry. Won't distract you."

"You're not distracting me," Scarlett said, which was the single least true sentence she had uttered all morning, and they both, for entirely different reasons, let it stand.

The rest of the lesson passed in a silence that Leo found mostly comfortable and Scarlett found anything but. He worked his problems. She worked hers, and three other invisible jobs, except that now her pen kept stalling, her gaze kept drifting a few degrees to the left toward the boy at the next desk and then snapping guiltily back, and the neat architecture of her notes developed, for the first time anyone could remember, the occasional crossed-out line.

When the bell rang, Leo gathered his things, quietly pleased to have survived a whole period without further disaster. He was just standing, slinging his bag over his shoulder - carrying it himself, as ever - when Scarlett's voice stopped him.

"Evans."

He turned. She had risen too, and she'd reassembled herself entirely; the President was fully back in command, folders squared in her arms, expression set to a businesslike neutrality that not even Leo's noticing could find much of a crack in. Only the faint lingering color high on her cheekbones gave anything away, and she was clearly betting he wouldn't mention it.

"As Student Council President," she said, in the brisk tone of someone reading from an internal memo, "it falls to me to ensure new students integrate properly. You're unfamiliar with the school, its layout, its procedures. It would be... inefficient to leave that to chance." A small pause. "I'll show you around. Help you settle in. It's a Council responsibility."

It was, in fact, not a Council responsibility, was not in any bylaw, and had never once been extended to any of the dozens of other new students who'd passed through Silverleaf. Scarlett knew this perfectly well. She had constructed the justification on the spot, out of pure necessity, because the alternative - admitting to herself that she simply wanted to be near the boy who'd handed her a pen - was unthinkable, and the President always had a procedural reason. The President's reasons were never personal. That was the whole point of being the President.

Leo, of course, heard none of the subtext. He heard only that the one person in the building who hadn't dissolved into baffling fizzing fluster - the cool, competent, sensible girl who he'd decided was the closest thing to normal he was likely to find here - was offering to help him learn his way around, which was genuinely, enormously kind and exactly the sort of practical, no-fuss assistance he could actually use.

His face broke into a smile of pure, uncomplicated gratitude.

"Really? That'd be great," he said. "Honestly, thank you - I've been a bit lost. That's really nice of you."

That's really nice of you.

Scarlett's jaw tightened almost imperceptibly. The color on her cheekbones deepened by a degree. She looked, for a flicker of a second, like someone who had set a small careful trap and walked directly into it herself.

"It's nothing," she said. "It's procedure." She turned smartly toward the door, folders clutched to her chest like a shield. "Come along, then. We'll start with the layout of the east wing. Try to keep up."

And Leo, slinging his bag higher and falling into step behind the straight-backed, slightly-too-pink figure of the Student Council President, thought, with the warm relief of a drowning man spotting solid ground:

Great. At least I've made one normal friend.

He had, in fact, just acquired the first and most organized casualty of a war that hadn't started yet - and the only person in Oakhaven, besides himself, who had any inkling at all that something significant had just happened over a dropped red pen.

They walked out into the corridor together, and behind them, all down the row of desks, thirty pairs of eyes followed the new boy and the President out the door, and the whispering began again in earnest.