In Harry Potter and the Order of the Phoenix (book 5), Umbridge wants to use a magically enchanted black quill on Harry that makes him write lines with his own blood, painfully cutting the words into the back of his hand and scarring it.

Quick Scoop: What Umbridge Tries to Use on Harry

Dolores Umbridge’s preferred “punishment” for Harry is a cursed, blood‑quill- like pen.

Instead of ink, the quill carves the sentence he is writing (notably “I must not tell lies”) into the skin on the back of his hand, and the words appear in his own blood.

  • It causes sharp, repeated pain each time Harry writes a line.
  • The cuts slowly heal into scars, leaving a permanent mark on his hand.
  • It is essentially a form of magical corporal punishment disguised as “detention.”

This is why those detentions with Umbridge in book 5 are remembered as some of the darkest and most abusive moments Harry experiences at Hogwarts.

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