My sister and I have always been close even though she is the oldest in our family and I am the youngest which puts 7 years between us. Last week we had decided to travel together, Her husband had a conference in San Diego and she had mentioned that she was going up two days after him to spend a couple days, She invited me and my husband and we accepted.
We live an hour and a half from the nearest airport and after she dropped her kids off at our parents house we all traveled together, We arrived at the airport and found our flight was delayed, Then delayed more then canceled then back on, As it turned out the flight had mechanical problems and we had to wait for another plane so they put us up in the hotel airport until 6:00 am the next morning but only put us in a double room. My sister and I didn't really care and my husband works with/for her husband and did before we were together and has been around for 10 years so he and my sister get along well and we decided it was fine.
We had supper and some drinks and a few more drinks and around midnight we decided we better go to bed, We were all pretty drunk and after my sister changed in the bathroom my husband quickly stripped to his underwear and jumped into bed. My sister came back out and crawled into bed then rolled over and looked at me saying good night and we both replied good night, Me and my husband have only been married for a year and still...Quite a bit by my sisters standards. After my sister fell asleep we were messing around and my husband pulled my sweats down sliding into me from behind.
We were quietly humping and I slipped my sweats off then laid on my back and he got on top, We had the covers pulled up and were being quiet but I got off kind of quick then whispered to him to hurry up, He grabbed my butt cheek and reached around touching my...Yeah. I pulled his hand away and whispered "No, Just hurry up", He whispered back about how it would help him finish and I said no. He kept trying and I kept saying no when suddenly my sister rolled over, Looked at us and whispered angrily "Just let him stick his finger in your butt so he can come and we can all go to sleep".
My sister rolled back over and shoved a pillow in front of her and tossed a leg over it pulling the covers off her butt as she did. My sister has always had a nice butt, Growing up all my guy friends used to drool over her and even my husband has mentioned that after having kids her butt is "Phenomenal", My husband looked at me, I looked at him and he started stroking again, Probably 10 strokes in while looking at my sisters butt he gave a couple deep strokes and finished. He was still on top of me breathing heavy as my sister looked over her shoulder, Said "Good?", He nodded and she flipped the covers over her butt.
I was kind of in shock, Embarrassed, Surprised, and maybe a bit drunker than I thought but I went and cleaned up, Came back and they were both snoring so I crawled in and went to sleep. In the morning my husband went to get us coffee and while he was gone my sister rolled over and looked at me, Turned beet red and said "Oh my god, I am sooooo sorry about last night, Apparently that wine hit me harder than I thought", I burst out laughing and so did she then we giggled like little girls about the whole "Butt show" thing and when my husband came back he walked in, Turned beet red and said "Well...better get going" and we all packed up and got to our flight.
My sister told her husband about it and he laughed so hard he couldn't catch his breath and almost fell out of his chair, Needless to say we didn't share a room in San Diego.