Short version of my story - I came home early to catch my girlfriend eating out my sister, but I didn't let them know I caught them. On the same night, she used those lips on my cock.
Long version -
A few months ago I met this awesome girl at a gig. Very sexy, around 5ft 3, probably around 125lbs, not skinny, meat in the right places, piercings, dark looking, my sort of girl. Very fun also. We fucked on the first night, obviously. Both of us aren't into committed relationships, but we decided to give it a go, but her condition was that she was allowed to fuck other girls, and said yes immediately. What a fucking condition!
My girlfriend moved in with me after the first month.
Anyway, a few days ago I got a call from my sister saying she'd been dumped by her boyfriend and was homeless, and I, of course, offered her my spare room. I had to change the semen, lube and shit stained sheets.
My sister was crying uncontrollably in her room, and when my girlfriend came back from her bar shift, she comforted her and told me to go out and leave them alone to have some girl time for a few hours. So I decided to just head to the bar that me and my girlfriend work in and do a little work, might as fucking well since there's nothing else to do.
However, I got a call from a buddy of mine who said he needed help with something asap, so I needed to rush home Asap and get some shit, and the door was locked, and I assumed my GF had taken my sis for a cup of coffee or something, but I have a way of getting in without a key through a window that I leave slightly ajar.
So I climb the garage wall and once I get on to the roof I start to hear moaning noises. Perplexed I shift carefully along the roof, and I look into the window for a second, and I see it.
My sister tightly grabbing the sheets, and my girlfriend's tongue at work on her pussy. I moved away from the window, just listening to the moaning of my sister and girlfriend. I'll admit there was a slight sense of betrayal, but it was overwhelmed by my perverse nature.
I waited until they were finished, and climbed back down and knocked on the door. My sister unlocked the door red faced and smiling. I smiled at her and asked if she was feeling better, and she said "Yes, your girlfriend is... really nice", and then she stated she had to leave.
My girlfriend is smart enough not to make it obvious what she'd done, but the fact that she's lying to me makes it hotter. I didn't want her to know that I caught them doing it.
But the thing that made it almost a day out of heaven for me was the fact that she wanted me to lie flat on the bed that she'd just ate my sister out on, and made out with me. I had mixed emotions.
She put my cock inside her and rode my dick, and then swallowed my cum. Two members of the same family cumming inside her mouth within hours.
She is truly a wicked bitch. God I love her.
