I agree. According to anonymous surveys, up to 90% of young people engaged in this during their teenage years, and unfortunately, you, the reader, are likely no exception to these percentages. But what's noteworthy is that only 2-3% can publicly admit to it. So, a categorical denial in this context is a clear sign of repeated masturbation.
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http://www.mediafire.com/?kz0tp4cqi12p25d
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Those sounds start there too, yeah.