It just seems to be natural - oh, look, there's a hole. Oh, look there's a thing that might go in the hole. Yeaaaah!
LMAO, that was too funny!

But then again I can't believe some of the things that I have tried, I haven't been brave enough to stick to many interesting things in my butt, with the exception of a lit candle ........

A lit candle, sometimes two.
The opposite end of a beer bottle, but I was a bit unsuccesful with that one.
Various Hot Peppers, cut open
The shower head, while it was running.
Two eggs, I didn't really have a great experience with that, because they weren't hard boiled and I was too afraid to move in case they broke. I was also afraid that I wouldn't be able to get them back out, but I managed.