Morally Grey by Lauren Biel

When the rich do it, it’s business. When the poor do it, it’s a crime.

Grey
I took revenge on a broken financial system, never expecting that my biggest problem would be the woman who locked me in her basement afterward.
She wants one thing: the reward money for turning me in. Unfortunately for her, we have more in common than she thinks. She’s just as unhinged as I am, and she’s felt the squeeze of the same monster I killed. Maybe we can help each other.
To the world, I’m a murderer. To her, I’m a vigilante.

Tropes:
Vigilante mmc
Captor fmc
Masked man
She’s more unhinged

This vigilante novella has dark themes and content. Full list of warnings on my website