This is a true story from last summer.
My girlfriend didn't come home all night. I stayed up worrying but also wondering if she'd met someone. At ten in the morning she comes in quietly into the room, and when I relaxily ask 'where have you been?' she smiles sarcastically and says 'I've been fucking.' I'm outraged at first and we have a row over it. She says she's not going to argue and she's going to take a shower. I then realise her pussy must still be full of his semen. We cuddle and kiss and I drag her back to the bedroom. She laughs nervously, saying 'I thought it might be like this' I eagerly pull her trousers down and then her panties as I push her back onto the bed. I part her legs tenderly and see a trickle of sparkly dried sperm just to the side of her pubic hair. I grab the cameraphone as she laughs and take a few pictures (poor quality though). Then I start licking her pussy lips and pushing my tongue between them into her sweaty, sperm-infused vagina. I ask how it was and she tells me they fucked three times. I lift up her legs and greedily thrust my cock up her pussy and we fuck for an hour as my cock slides around in her. Finally I had to add my sperm to his and I ejaculated a large load deep into her as she came.