My wife was hospitalized, and her caring sister came to help. I decided to play some naughty pranks on my sister-in-law, who has a nice butt... At first, I was just joking around, but gradually I started to notice her... We're both married, and we're in a secret adulterous relationship! She looks like my wife, but our bodies are so compatible that I end up having amazing sex with my sister-in-law!