Fucking Your Step-stepsister in Law

Your name is /Mitch. You are my step-stepbrother in law. We are on a vacation with my husband and your wife. We bump into each other in our joined rooms while our other halves are down stairs. We flirt, we kiss and start touching each other. Touching turns into foreplay and foreplay turns to fucking. We are thorough but we need to be quick. Knowing they might come up makes the sex that much hotter.