Upper Sixth Invocation had to master the fourth-order practical before the mocks whether they liked it or not, as well as covering triple arrays and advanced exorcism. It was a wan, unenthusiastic group who greeted Walden in the seminar room for their first theory lesson of the half term. Mathias had his head down, meticulously drawing more ballpoint geometric patterns on the dotted inside cover of his lever arch folder. Aneeta kept fidgeting with her glasses. Nikki was not taking notes and not asking questions. She sat by the window and looked out at the grey morning as if she was hoping the classroom would disintegrate into the clouds. Will turned up late enough that Walden gave him a demerit, laughed too loudly at the atmosphere, and attempted a few jibes of banter which, unusually for him, were misjudged badly enough to cross the line from ‘schoolboy nonsense’ to ‘actively nasty.’ Just as Walden began—“Highly inappropriate, Will, I am not impressed, and that’s another demerit”—Nikki turned away from the window and said explosively, “Could you maybe just not be such a shit all the time?”

“Wow, okay, aggressive much,” began Will, and Nikki abruptly stood up, grabbed her schoolbag, and then—oh, Walden’s heart went out to her—managed a tight and miserable little, “Sorry, Dr Walden, I’m just—sorry,” before she gave up and fled the classroom.

“I’ll go,” said Aneeta at once, getting up to follow her, leaving all her things on the desk.

Walden immediately and automatically did the necessary mental calculations. Objectively, both Nikki and Aneeta could afford to miss a short section of a lesson—they were conscientious, ambitious young women, and Walden had already given out the booklet she’d written for the class on triple arrays. Both of them could probably teach themselves the theory from there. In fact, Nikki had already taught herself the theory, hadn’t she? It had been a triple array, competent but simply not strong enough, that had stood at the heart of Old Faithful’s incursion. So Nikki taking a moment out of the room was not an academic problem.

And with teenagers, as well, there was the question of dignity. No one wanted to have an emotional breakdown in front of an authority figure and a classroom of their peers. A comforting hug from a friend in the girls’ toilets, and a chance to fix her makeup and gather her pride before returning to the lesson, might be exactly what Nikki needed.

Or it might not.