As training continues on the Mithraeum, Ianthe's sword-fighting reaches a breaking point. Augustine has lost patience with Ianthe because her uncertainty also affects the dead soul of Naberius Tern when Ianthe travels in the River, weakening the sword arm meant to defend Ianthe's body. Harrow, by contrast, is treated with less scrutiny because the others increasingly regard Harrow as already doomed.

Harrow's eighteenth birthday passes unnoticed, marked only by Harrow's private memory of the two hundred children whose deaths made Harrow's birth possible. Around this time, Harrow accepts that Ortus the First, the Saint of Duty, must die. Harrow no longer finds his Ninth House name troubling because Harrow now understands Anastasia's influence on Ninth naming customs, but Harrow comes to fear Ortus after recognizing the nature of his power.

Harrow has fortified Harrow's quarters with intricate bone and blood wards, especially in the foyer, windows, crawlspaces, plumbing, and bathroom. While bathing, Harrow notices grey dust in the water and realizes the central bone ward has been reduced to inert powder. Ortus the First then breaks into the room, having neutralized the wards completely, and attacks Harrow with spear and sword while Harrow is naked, unarmed, and cut off from almost every prepared defense.

Desperation makes Harrow abandon distance fighting and use Harrow's own living bones as weapons. Harrow grows spurs from the bones of Harrow's hands and wounds Ortus, but Ortus strips the thanergy from those fresh bone growths, making them brittle and useless. Ortus batters and cuts Harrow badly, but Harrow uses loose teeth as enamel projectiles and drives one into Ortus's eye, forcing him to retreat.

Harrow survives the attack but understands the deeper consequence: Ortus can bypass and destroy Harrow's necromancy because he is effectively a thanergy void, making him the ideal enemy for a Ninth House bone adept. Ianthe briefly appears at the doorway, and Harrow realizes that if Ianthe offered comfort, Harrow might surrender to a dangerous dependence on her; instead, Ianthe makes a crude remark and leaves. Severely injured and shaken, Harrow declares that the Saint of Duty must die, and the Body agrees.