Brutal Prince (Brutal Birthright, 1) by Sophie Lark

He’s No Prince Charming…
Callum Griffin is the heir to the Irish Mafia. He’s ruthless, arrogant, and he wants to kill me.
We got off on the wrong foot when I set a (very small) fire in his house.
Our families believe a marriage pact is the only thing that will prevent all-out warfare.
I think I might need to murder him while he sleeps.
This would all be a lot easier if Callum wasn’t so damned good-looking.
But I’ve got a lockbox around my heart. Because even if I’m forced to marry him…
I could never love a brutal prince.