Forbidden Love: Life of a heartless human

Does a human being exist in this world that doesn't have a heart?

Well, that's the fate of a girl, she's poor and innocent, and she hasn't even hurt a single fly before but what could the gods give in return for that?

She's heartless, she lives on an artificial heart because she doesn't have enough money to get a transplant.

But when a billionaire suddenly comes into the picture, a cold and dangerous Billionaire who is only warm and friendly to those he loves

He offers her a one-time job his only rule is not to fall in love with him under any circumstances.