Sex with daughters-in-law is a very pious and sacred relationship which is promoted by Quran and was practiced by our prophet, the perfect man. Our prophet had a beautiful daughter in law Zainab, wife of his adopted son known as Zaid Bin Mohammed. One morning he walked into her room looking for his son and ran into her while she was just waking up and was still in her birthday suit. He liked what he saw. To make a long story short, she was in his bed within a few days.