I am secretly dating my adult stepsister without our parents knowing. Normally we can only steal brief moments of affection, but when our parents leave on a trip, all our restraint collapses. Alone together for two days, we fuck again and again from morning until night, growing closer with every round. We are afraid of pregnancy, yet still keep creampieing during our forbidden time together. Living under the same roof as my lover feels incredible. An adult stepsibling role-play.