So me and my husband went to my sisters house to pick up some groceries she had gotten for us. After some time he went to the bathroom. Me and my sister were talking about new events in our life when I realized my husband has been gone for over 20 minutes now. I told my sister I was going to go rush my husband. I walked by my sisters room since it’s next the the bathroom and I heard a strange noise. I cracked the door open a little and I saw my husband… dick in his hand jerking off and sniffing my sisters dirty panties. I stood at the doorway watching him jerk off until he came and I was making sure I made no noise. I thought It was hot watching him betray me like that. I went back to the kitchen where my sister was and a few moments later he followed. I haven’t brought it up yet but I will soon