Heartless by elsie silver

Working as a nanny for the world's grumpiest single dad should be simple…except she can't keep her eyes off him. And he can't keep his hands off her.

Cade Eaton is thirteen years older than Willa Grant, and he barely looks her way, even though she's living in his house for the summer. That is, until she gets him into the hot tub one night for a game of truth or dare. Then, all bets are off―and so are their clothes.

Cade is gruff, a little rough around the edges, but broad-shouldered ranchers with calloused hands and filthy mouths are this city girl's kryptonite. So who is she to resist?

But it's in their quietest moments together that he softens. It's in the unexpected way he takes care of Willa that she realizes his hardened exterior is just a façade. And it's when she watches him go all sweet with his little boy that she starts to fall for him, whatever the consequences.