NYH-039 - My sister kept teasing me with her panties, so I finally snapped and took her

My sister, who always bullies me, was driving me crazy with her constant flashing. She knew I was getting hard, and she was secretly masturbating to it. When we were left alone, we ended up watching each other, and things got out of hand. The thrill of breaking the taboo made it impossible to stop, and we ended up crossing the line.