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She comes out of the bathroom from the shower, applies some cream on her body, and now wants to sit down to finish getting dressed, but, oh no!!! Now she feels something strange in her butt! (You hid in her chair, and since you were so tiny, she couldn't see you, so you were ready to enter her ass as soon as she sat down) She looks in the mirror to see if there was anything there, but she doesn't find it, so she runs off to the bathroom to try to get it out... (You're still clinging to her ass, because now that will be your home.)