.. She was still clutching me tight whimpering contently as her muscles kept trying to grip me and hold me still as her body wanted to control what wa... pleasuring her ... I put my lips to her ear still pounding her like crazy and growled ' I'd love to shag your arse like this later on .. if you let me ' ' yesssssss .... Yes oh god yes .... Hurry darling I need to .... Oh fuuuuuck ........' she stopped talking as her second wave ripped through her I think brought on by bucket load of spunk. "Fuck yeah," I yelled as I was about to come."Kurt? What the hell is going on here?" I looked up at the sound of this and was mortified to see that my sister had come into the room and was staring at me open mouthed. I just started at her completely red. I didn't know how much she'd heard but however much couldn't be good. I'm ashamed to admit that I blew my load and came all over my chest. I started to talk, but my sister just help up her hand to stop me. She just came around in front of me,. You're looking to see if I am done. "Oh no," I say, "You're not done yet slut."I pull my cock from you, and you shudder again. I roughly twist you over onto your stomach, and I smack your round ass peeking out from under your skirt. I spit on your ass and move my hands to it, guiding the spit down your ass crack, until I find that tight sphincter, sealed shut against me. I pop a finger in without hesitation, and you turn your head to the side to make sure I can see you shaking your head no. Oh. Ho hum. The next day I had to go to the library. She was obviously bored, and spent an hour at the index files while I tracked down a set of Heisenberg lectures. On the way to the front desk, she asked me if she could check out some books. Sure, why not. She wouldn't tell me what she was looking for until we got to the stacks she was looking for: human sexuality. She explained that her home town library didn't have any books on sex. She blushed deep red when she asked me if I was still.