The Fireproof Girl

Sophie was abandoned at birth and grew up neglected and abused. Her only friends were computers, until she met Cole Hunter. He became her everything: brother, protector, and partner in crime.
She believed that nothing could ever tear them apart. Until it did.
Years later, when news of Cole's murder reaches Sophie, she completely snaps. She will tear down heaven and earth to find his killer, even enlisting the help of her ex-military ex-boyfriend.
But the more she gets involved with the investigation, the more she puts herself at risk...
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When Cole was nine years old, he watched his whole family burn to death in a house fire. He became obsessed with architecture, and rebuilding his life.
Sophie became his secret weapon. Protecting her was his purpose. But Sophie was damaged right from the start, and it was easy to scare her away.
He always feared that he wouldn't be able to protect her from her enemies, or from herself...