Sharing Is Caring

I've been holding onto this one for a while now. I went out drinking with my sister about 10 years ago which was rare as we don't get on but it was fun and we both got more wasted than expected and she insisted I stay the night .
T's husband had been drinking as well while having guys night playing online but had finished when we got back and was laughing and joking as we fell through the door and almost forgot I was there as T stripped to her underwear.
There was no way he could hide what he was thinking when he saw her and I must have been staring as I didn't even notice him holding her up and smiling at me.
He asked me to give him a hand and T just laughed and said I bet she'd love to before grabbing his crotch.
So we got her to bed where he straight away stripped her underwear off as if I wasn't there and left her with her legs spread and offered the spare room which I excepted but I started feeling really off balance and fell into him so he helped me through and I just blurted out you gonna help me into bed to and dropped my dress, he chuckled and said he would but T wouldn't be happy, but that didn't stop me taking off my underwear as we got there and pulling his hand to my pussy, which he quickly pulled away but I could tell he wanted more as his dick was clearly hard and visible through his shorts.
He put me on the bed said goodnight and as he closed their door I saw his shorts drop.
I lay there in bed rubbing myself as T groaned and cried out with pleasure as he fucked her for a good hour then the door opened and I pretended to be asleep but could see she was out cold and he walked through the hall still hard and naked to the bathroom as he came back I let the cover slide to the floor and he came over to cover me and his dick got hard as he saw me so I knew he wasn't spent and drunk brain suddenly had an idea.
I waited maybe an hour and heard they were both asleep and made my move. I crept across the hall to their room and almost laughed as T was down on the floor now and her husband was half covered with his face covered which was perfect. I carefully got my pussy over his face under the cover and started to lick and suck his cock enough that he started to eat my pussy with no questions. I was so excited already I'm pretty sure I came twice almost instantly one after the other then doing my best impression of my sister I told him to keep his head covered and no peeping and moved to ride his cock.
He did as he was told and I had a massive orgasm and had to try not to scream.
He emptied his balls deep in me which then sobered me up enough to realise he wore a condom before which was still on the floor. I got lucky as he fell back asleep straight away so I cleaned his cock with my mouth and in a moment I'm really not proud of I got over my sister and got as much cum as possible out of me and on to her especially around her pussy and mouth so he wouldn't think it wasn't her.

The next morning I heard them talking about it and she said she didn't remember any of it but as she was covered she must have. T sober was a lot more prudish and got really annoyed at me sleeping naked with the door open, she passed me off with little comments here and there through the morning so any guilt I had for what I did was short lived and I was actually glad I fucked her man and wish I could have done more