I've been dating my stepsister in secret, keeping it a secret from my parents. Normally, I'm just being careful not to get caught by my parents, but on the day my parents leave the house on a trip, I can't stop! My normally restrained rationality collapses and I just keep doing it with my stepsister over and over again! And the more I do it, the deeper the bond between me and my stepsister becomes! To be honest, I'm scared of getting pregnant, but I still do it as if it's normal to cum inside her. The feeling of having a lover under the same roof is the happiest thing ever.