Pretty young Nelly Kent decides to skip her college classes because she has a big test that she has not studied for. Thinking she will be home alone, she is shocked when she finds her stepbrother in the living room. He has no classes today, but knows that she is skipping hers. Nelly knows that he will tell their parents if she doesn't think of something really quickly. She sits in his lap and begs him not to tell them. Sis offers to clean his room for a month, wash his car, do his laundry, anything he wants. He is looking at her in a way she has never seen and sister feels something hard in his lap. Seeing the smile on her face, he reaches out to feel her tits, watching her nipples get hard through her tanktop. Nelly knows what it will take to keep him quiet and promises to let him do whatever he wants if he will just keep her secret from their parents. He quickly agrees and Nelly takes brother's fat cock out of his pants. It is bigger than any of the boys she has dated and she finds herself quite horny while sucking it. As she squeezes it tightly between her tits, Nelly asks if he would like to put it into her tight pussy. She is willing to do what it takes for him to keep her secret, but also wants to fell that big thing inside of her. After just a few strokes they are interrupted when mother comes home. Nelly runs off to hide. The next morning he finds Nelly in bed and plays with her pussy. She stirs but does not awaken until he slides his cock into her tight hole. Sis wakes up and is worried about getting caught, but does not want him to stop what he is doing. His deep strokes fill her pussy and she wants to feel every inch. No one is around to interrupt them this time and she rides his big cock until he pulls out and explodes all over sister's pretty face. He promises to keep her secret, but now they both have an even bigger one to keep.