She had pink hair.

She had pink hair that won't turn back to its normal colour.

...

WHY in the world did Nora have to practice those spells?! And why won't her hair just turn back? Yes, she liked the reddish - dark pink shade, but she couldn't just walk around the castle looking like that!

She snuck into the girl's bathroom, with her hair hidden under a knit cap, and took it off only when she was sure that there was no one around. Wasn't it enough to be the weird girl with a lizard as a pet, instead of an owl or a cat? Did she really have to have PERMANENT pink hair as well?!

Holding her wand and staring at her dark pink locks, she finally closed her eyes and tapped her head twice. "Intaris." She opened her eyes to find it looking the same. Why? What was wrong?

...

After a few more times of trying, she was about to give up and go to professor Magnus or someone (but surely not professor Lafay, because she had a feeling that the head of house would just turn her hair green to match her house colours)...

... she opened her eyes to face her light brown hair.

It was back! But what took it so long?

Never mind that. As much as Nora liked the spells, she knew she won't try them again. Ever.