"It's okay to have sex with a condom, right?" This led to the condom breaking and me having sex with my sister without a condom. Report on this incident! HUNTC-073

My younger sister learned how to use a condom in her health and physical education class, so she asked her older brother to help her practice. I couldn't refuse, so I let her take off her clothes and put on the condom. I thought everything was going smoothly, but then my sister suddenly changed! "I did use the condom correctly, so it's okay to have sex, right?" she said, straddling me! However, the condom broke halfway through! And my sister even felt pleasure, so I ejaculated inside her. My sister and I then started having sex without a condom... Was this all beyond our control? My sister wanted it so badly!