Here is the envelope. Looks like the sender is a supporter of stopping breast cancer.
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Here's the back. Puppy and kitten stickers!
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And inside...
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Good old American porn.
I have done similar things with obnoxious mailings from credit card companies, except normally I just take the stuff out of one credit card application and switch it with the stuff from another. This was genius.
And it was real porn. I just arranged the pages so the really good stuff was face down. And I did not get excited by the content. I just had to go pee right afterwards.