Deathless Death: Amartya's Story by Lolly Sparrow

When Amartya spurns Orpheus’s proposal, she finds herself the victim of a curse forged by a malevolent necromancer, and a single bite from Merlin, a divine-touched mouse, condemns her to an existence between life and death.
Yet instead of making her a victim, undeath turns her into something more.
Using her newfound strength and longevity, she turns her curse into justice, hunting true monsters; killers, abusers, and the wicked who wear humanity’s mask, across centuries and continents, with Merlin at her side.
She is the monster even monsters fear: undead, forever in a deathless death.