Three of Us by Ella Goode

Olivia is ready for two things: college and her men.
Despite dating the Audley twins since she was fifteen, it’s been a chaste relationship. No matter how she tries to tempt them.
Her men haven’t even kissed her, and she’s tired of waiting. The minute she hits campus where the two men have been hiding out for the last two years while somehow still keeping tabs on her every move, she will shake their world.
Levi and Zeke made a promise to Olivia’s mom they wouldn’t touch her until she was ready. They’re not sure what that means, but they know they will wait forever just to have her. The problem is that Olivia keeps testing their vows. It’s hard not to give your girl what she wants when that’s all you’ve ever wanted to do.
The minute the clock turns midnight, though, all bets are off.