My sister-in-law and I are very aware of each other. We finally kissed while our parents were away on a trip... But she refused to go further, saying, 'Once we start, we won't be able to stop.' However, I couldn't hold back, so we were just supposed to rub against each other without penetration, but I couldn't stop the urge to insert. My sister-in-law felt the same, and as we rubbed against each other, we pretended it was an accident and went for insertion! We couldn't stop and had intense, deep thrusts, ending with internal ejaculation. Before our parents came back, we had dozens of rounds of internal sex.
