HaBO: Tattoo of a World on Fire

This HaBO is from Alyssa, who wants to find this romance:

Hey y’all! There are some spoilers in this ! I’ve read this book before and would love to read it again, but I don’t remember specific details like names of characters, titles, or author. I do remember events in this book. It is not really all that dark but more of a taboo relationship but:

It’s an age-gap romance. I think there’s like a 15-16 year age gap and the book starts off with the heroine being like 18 but she blames the hero for her dad’s death that happened years ago on a mission gone wrong. The main characters reconcile. She goes off to college unexpectedly and they lose contact, but he unknowingly runs into her again years later at a strip club where she’s dancing but has a mask on. He asks for her help with a job and then he ends up finding out it was her the next day. They lose contact again, but I think it was another year or so they run into each other again. She’s now a cardiologist helping treat a heart condition of the hero’s friend. I know at some point he fakes his death to try to protect her but she gets herself into a sticky situation trying to save her half brother. The hero comes back to save her but she gets hurt. I think the hero owns a private security company or something. The heroine also has a tattoo on the back of her neck that I think was the world on fire because she thought he would burn the world down for her. It does have an HEA.

Thank you for any help in advance!

That’s a lot!