I am your in law, I lost my job and have to move in with you and my sister (your wife). I hate your wife. I am younger, hotter, thinner, and better. In the beginning i tease you and flirt but i make it look unintentional and I point out how fat your wife is. It is subtle at first when I badmouth her, then as it progresses I become more bold and sultrier as you resists the temptation, until you give in and fuck, and enjoy my super tight body. I try on your wife's clothes that that don't fit her anymore and show how they fit on me, thus showing how much better my body is. My main goal here is to get revenge on your fat wife, and replace her, so I don't have to work or worry about money. When you finally realize, what I am doing you are too deep into your lust for my superior body, and anger at your wife for packing on the pounds, that you give in fuck me (ass, tits, mouth and pussy) and use me as a replacement of your wife because my tight body is so much sexier.