On top of that, there were the hours upon hours she spent maintaining Chetwood’s magical infrastructure. Children were such easy targets for opportunistic demons that even ordinary schools needed a couple of solid incursion wards on site, just in case. One of the things Walden had brought in as Director was the sixth form volunteering club, who went around the local primary schools repainting what were usually faded, half-arsed protections against demons. Magical specialists were expensive, and waiting for the county council to get around to hiring someone was a mug’s game. But at least in a normal school, the worst you were likely to encounter on the demon front was a determined imp, encouraged by a talented but inexperienced child who’d watched too many unhelpful videos on the internet.

Chetwood, with its long magical history, and six-hundred-odd half-trained adolescent magicians living on site, was a different kind of problem. Ordinary schools did not have a dedicated team of Marshals stationed on site. Ordinary schools did not need incursion wards in every building. But Walden’s biggest problem was not the mobile phone incidents, the difficulties of politicking with Marshal Kenning, or keeping the incursion wards up to date. All of those paled next to her most vital responsibility: managing the intricate system of nineteenth-century wards, which had been the height of cutting-edge sorcerous-industrial invention around 1855. They depended on an enormously complex set of old-fashioned thaumic engines, built into and impossible to move from a large room adjoining the Headmaster’s suite in Brewers Hall. The mechanisms were more than a hundred and fifty years old, comically clunky, inherently vulnerable to demonic possession, and a nightmare to maintain. They were also so absolutely integral to the way the rest of the school’s magical defences worked that if they failed, there was a good chance that Chetwood School would just collapse out of mundane reality altogether and disappear into the demonic plane, taking six hundred children with it.

No pressure, the Headmaster had remarked to Walden wryly when he hired her. David Bern had been selected by the school governors to attempt to save Chetwood’s faltering academic reputation, and he was doing a good job on that front, but his background was geography, not sorcery. That was why he lived in a rather nice five-bedroom house in Chetwood village, while Walden lived in the old Head’s suite, sleeping in the room next to the thaumic engines.