It's been a few months now since my first encounter with my little sister Rachel. Almost every chance we get to be alone, we're fooling around. We can't seem to get enough of each other, and it's like Rachel's developed this habit of making me cum as often as possible. She never wastes a drop of either, it's like she's hungry for it.
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One time, our mom was out gardening out back. I was standing at the kitchen sink, where a window looks out into the backyard. I was watching my mom gardening. Rachel was on her knees at my feet, sucking my cock while I kept watch. She said she'd wanted to see if she could make me cum before Mom finished gardening.
"I want to swallow your cum," she told me, taking me out of her mouth and jacking me off as she spoke. "I want my big brother to cum in my mouth so I can drink it." She closed her eyes and kissed the tip of my penis, put the head in her mouth, sucked it a little, and kissed the tip again.
"Oh yeah?" I asked her. "You like drinking your big brother's cum?" She put me back into her mouth.
"Mm-hmm!" she hummed as she kept sucking. She took me out of her mouth again. "I'd make you cum all over me," she told me, "but we don't have time to get messy. How's Mom's gardening coming along?" She pushed my cock all the way down her throat and kept it there. She made little choking sounds while my dick throbbed in her mouth.
"She's trimming the hedges now," I told my little sister as she started sucking again, taking it all the way down, and then coming all the way back up again, until her lips were around the tip of my cock, but never taking it out of her mouth. "But you better keep going. I want to finish before Mom's done out there."
She kept sucking, clearly trying to make me cum as fast as possible. She took it out of her mouth, spat on it, jerked it off a couple times, and then resumed sucking. The moment had arrived.
"Don't stop, I'm cumming," I told her. At this moment, I saw mom kneeling down and starting to pack up her gardening tools. Rachel moaned as I started unloading in her warm mouth. After a few seconds, I heard and felt her swallow. Our mom was standing up now, and making her way to the back door. She saw me through the window. We smiled at each other while I was still cumming in my sister's mouth. She swallowed again, happily drinking her brother's cum.
"Rachel, Mom's coming back in," I told her as my orgasm was coming to an end. Rachel swallowed one more time, and smiled up at me while licking her lips. I was getting my pants buttoned up when our mom entered through the backdoor.
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It was another Friday evening. Mom was out at her Yoga class, which gave me and Rachel about 2 hours of time alone. Time enough at last, time enough to do anything we wanted, and no one else would have to know.
Rachel and I were snuggling on the couch watching TV. We were talking and laughing about some drama that had been going on at school. Then she got sort of serious.
"David, I have a favor to ask from you," she said to me. "I don't think you'll mind, but you might think it's a little weird..."