I hate her and all but I hate hurting people and I don’t want to go to Azkaban for using an unforgivable curse.

Make her write in her own blood for hours on end, and when she’s at the brink of death, sectumsepra her, and then give her the dementor’s kiss

I don't want to go to Azkaban

Maybe let her drink the Veritaserum

Imperius curse to make her use that blood ink pen for 7 years straight

She can rot in Azkaban.

Imperius to make her use the blood quill for a year to chop off her hands

Ew. But she deserves it.

Kill her is going a bit too far------------

Imperio/Crucio her until she tells all her secrets, force her to write in the blood ink pen, send her to Azkaban for a few decades and if she is still alive kill her.