Nothing what so ever, that's her personal business.. If she stimulated herself in front of you or others then tell her to go into her room if she's going to do that.. but if you were nosing about, then shame on you.. Bottom line: Blow it off (NO!! I didn't mean it that way!).
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Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them