Thin Lines (Donati Bloodlines #2) by Bethany-Kris

Calisto Donati

Calisto had never been a fan of pain, but he found it provided a certain relief. It was a high that couldn’t compete with anything else he experienced. That was why he fought bare-knuckled, why he drove fast, despite knowing he might crash, and why he still enjoyed looking at Emma Donati—no matter her current status. Pain felt good.
He might have been a fool for doing so, but as long as he got what he wanted from it, he didn’t really care. When he fought, he was given release. When he drove, he was given freedom. When he looked at Emma, he was given memories. All of them brought a certain level of pain. All three might kill him someday. Calisto glanced at Emma, taking her in again when she didn’t know he was looking. He realized then that only one might actually be worth dying for.

Emma Donati

Emma kept her gaze on the book in her lap, pretending like there wasn’t an argument going on across the room. She had become terribly good at acting like she didn’t hear.
Calisto watched her out of the corner of his eye while he argued on with Affonso. She was too focused on Calisto to care about their fight. His anger. The tightness of his jaw. Searing soul-black eyes. The two men were not the same. They might have shared blood, but their hearts were entirely different. One man never let her out of his sight when he was nearby. The other acted like she didn’t exist. This was what it was like, she realized, to be in love with someone she couldn’t have.

Calisto Donati would never be hers. This wasn’t a fairy tale that would end happily. They weren’t star-crossed. They were impossible.