You and your sister innocently stay in the same room again while your parents discuss something heatedly in the kitchen. Your dick is pretty hard now. You try to hide the bulge, but the extra hand movements only cause more problems. Your sister is watching you and your attempts to “hide it”. A smile forms on her face. You don't realize what is happening at all. Your mind is clouded, your thoughts are confused. The only thing driving you right now is your cock and the desire to release the tension. Thankfully you didn't have to think long about how to solve the situation, and your sister was already very quickly on your lap.....