One day my girlfriend invited me over and when I arrived I found her sister alone in the house. She was unbelievably beautiful and whispered in my ear, "I have feelings for you. Shall we have sex?"
I immediately turned around and walked out the front door and to my car. I found my girlfriend standing there. She hugged me and said, "I love you so much. You've just won my trust." The moral of this story: always keep your condoms in the car.