A regular visitor to my home has a back-door secret. I don't know who this person is, but I'm thinking it has to be someone familiar, who comes over fairly often, because I've spotted posterior prints all over the house. I do know it's not a member of my immediate family, because I have inspected all of them for the tell-tail signs. I have gotten to the bottom of the secret: a pierced left butt cheek.
How else do you explain why all the toilets are in arrears, with gouges in the same place on each seat? If this was from a cleaning product or process, the tush tracings would appear all over the seat. If this was from buttons or other hardware on pants pockets, the derriere designs would (presumably) be on the lids of the seats. And the kids aren't smart enough to do any kind of hindquarters hijinks that would be so consistent.
I was a little behind for a long time... the hiney heiroglyphics were like Krinkeland crop circles... butt now I have cracked the case. I beg you, Ms. or Mr. Fancy Fanny, next time, don't be a bum: please remove your rump ring. Be a sweetie and don't scratch the seatie.