Index · spell · book 6
Sectumsempra
A cutting curse written in the margin of an old textbook. Using it without understanding it is part of the damage.
Sectumsempra is not a classroom charm. It arrives as handwriting: a spell for enemies, tried by a student who wanted an advantage and did not know the cost. The result is a wound that looks like a blade’s work. The book that contains it is already deep into the series, and the inventor’s name is a reveal of its own.
The journal records the category — a curse that cuts — and leaves the scene in the novel. Canon fact: the curse exists in the story and is not a school-approved spell. Anything beyond that is plot.