Nice work, it’s great to see the thought, and I agree making abusers pay with their health seems fitting - they hared the health of their victims so you are delivering equal returns in all fairness, and you are preventing them from harming others as much as possible.
I took a similar route using Sorceress Cagliastro’s 29 Deadly Sigils book. That one’s probably got too much set-up for many, but it’s never failed me. There’s a specific sigil for “Make a betrayer pay with their health and wellbeing” (something like that I don’t have to boo to hand. The target has aged fast, broken his leg twice, then got thrombosis - expensive hospital visit, and is just generally not well despite eating well and working out.
There’s a smorgasbord of ideas in this post that’s a great reference: