I am 30 and my wife is 29. We were married 1 year ago. Whenever we have intercourse we used to see porn movies, and my wife enjoys that saying she attracts men in our area. I use her elder sister's (42yrs) name everytime while having sex with my wife.

She never bothers but asked me why I am eager for her elder sister? I told her, that I had seen her nude while bathing and that I am intersted in her. My wife says  she is also intersted in her (uncle) elder sister's husband.

What should we do? Should we talk to them and swap our partners occassionally?