Their Summer Intern by Jessa Kane

Zoe was only planning to work for her powerful stepbrothers, Jacob and Bridger, until she could gather enough cash to take the adventure of a lifetime. But the first time all three step-siblings are in the same boardroom together, an entirely different adventure begins to take shape. One that’s a little twisted…and a lot satisfying. Zoe struggles against letting these formidable men overwhelm her too completely, but they’re more than willing to fight the battle until she surrenders…and becomes theirs forever.