So, I was at the seaside...

[mattbuck]

...where there's lots of mud. There was a pipe leading out and I thought I'd walk on it, but found I couldn't get to it because of the mud... Long story short, I ended up wading in the mud and ended up horny so stripped off and had a wank. Got my trousers a bit muddy though....

I found the mud surprisingly heavy, and very variable in depth - one step I'd go a foot deep, the next it was only my foot deep.