In-Law Exam

My future sister-in-law was one of the prettiest girls I'd ever seen. She looked like a china doll. But she was also always seen as the sexual prude of the family, never openly talking about sex, always wearing "librarian" clothes, and lacking any sense of self confidence in her appearance. It turns out she wasn't a prude at all. In fact, she wanted nothing more than to have sex with her husband. But he was resistant and often turned her down. This cause her to grow extremely frustrated. Eventually, all of that frustration would boil over and burst. I'm glad to was there when it happened...