In the book, Bellatrix uses a knife to torture Hermione, but the inscription is never mentioned. The scene is described as follows:
> "Bellatrix raised her hand, and the knife flashed in the firelight. It sliced across Hermione’s arm, leaving a deep, ragged cut that bled freely."
The inscription is only mentioned in the movie adaptation, where it is used as a visual representation of Bellatrix's cruelty and the severity of the attack.
While the inscription itself is not canon, the scene serves as a powerful reminder of the prejudice and violence inflicted upon wizards and witches deemed "Mudbloods" by pure-blood supremacists like Bellatrix Lestrange.