I used to bust my mom with her hand in her crotch under a blanket all the time. I would walk into her bedroom or the living room and see the under-blanket action and her eyes would be closed and when I startled her she'd act like I woke her up. She thought she was slick and for years I didn't know what she was doing but once I figured it out it was like the rewind in "Sixth Sense."
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