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My 34-year-old girlfriend lives with her 18-year-old niece and her two kids. I see her almost every day but we do not live together. Since last year I notice that her niece acts strange around me, especially when we are alone. If we’re in the hall, she’ll sit very near to me, and while we’re talking, her hand will fall on my thighs, and her breasts will brush against me as she bends over me. She is very beautiful and sexy, and when she comes close I get turned on. I realize that she is doing everything to get me…