I Wish You Were Mine by Jessica Peterson

I know Tuck Monroe is trouble the second I walk in to interview for the nanny position. Six-four and covered in tattoos, he’s distractingly hot. He’s also grumpy as hell. But I need to pay for school, so I take a job as his daughter’s live-in caretaker and move into the apartment above his garage.
I fall hard for Katie, his adorable four-year-old. But I never expected to fall for my new boss, who’s a decade older than I am. Turns out there’s a heart of gold beneath Tuck’s broody exterior, one I work to reveal bit by bit. Casual small talk leads to late-night conversations I can’t get enough of.
No surprise our simmering sexual tension explodes with one deep, toe-curling kiss.
He tells me I’m his good girl; I tell him I love the praise. We give ourselves one night, and one night only, to explore the fiery attraction between us.
It’s the best sex of my life. But when I wake up, Tuck is gone, and life goes back to normal. Or at least I think it does, until I start to feel nauseous. Turns out I was right: my boss is trouble. The kind that comes with one night I can’t forget and two pink lines that will change our lives forever.