Sister in law

32m married, so i love my wife to death. But man when her sister comes over i just can’t stop staring. We have a 3 bedroom 2 bath and the guest bedroom and bath is in view of the kitchen at a certain angle (when washing the dishes) . Usually i don’t pay any mind but today i caught her coming out of the bathroom after a shower. She made eye contact saw me, staring and i looked away quick. When i looked back to see if she was still there she was smiling and opened her towel, i got to see her tiny perfect tits, her trimmed little pussy and my mouth dropped. I didn’t tell her older sister of course. I was later in the living room, just casually watching tv before bed. I played it off like nothing happened. She comes in, sits right next to me, and grabs my hard dick. She said oh wow, i heard about it but sissy was right. And got back up went to the guest room and she said thanks for the spank bank. I wanted to so badly, so so badly. She’s insanely hot!!! But i couldnt. Kind of regret not just pounding it out 😵‍💫