using your urine as an enema

[onestrangeguy]

I've seen these pants and there is a version without the pants. It sounded great until I got to think about the unthinkable...like what happens if you can hold the enima? ...does it blow back or worst still.... the dreaded unwanted fart ..could you end up with an inflated bladder ???

The reality seems to be that keeping all the components of this system in place is far harder than one might imagine.
Yes, in the original scenario there is a pair of pants that attempt to hold everything in place. But in reality they're usually almost a thong sort of pants and getting them to fit exactly right, and move with the body so that they hold everything exactly right just doesn't happen.
But plugs love to work their way out. One would think that a tight pair of pants would hold one securely in place. The fact is that the plugs still somehow find a way to slip out.
Then comes the sheath. This is not a catheter, so forcing something back in on this end is unlikely to happen. Quite the opposite. The penis is an amazingly flexible appendage that varies in size and shape more than any article of clothing can truly accommodate. The result is that unless you stay fully erect, which isn't likely to happen over a lengthy period of time, the sheath won't maintain a tight seal on your member.
As for the fart. It will leak out of whatever openings that it can and will find. If you can't hold the liquid... well, some might back up and inflate the sheath in front. Beyond that i would expect that in reality it too would leak out around the edges. I seriously doubt that even the slightest drop would find it's way back to your bladder.
I do congratulate you on some interesting thoughts though. You certainly do present some entertaining thoughts.

[niborg13]

i have modified my idea since urine in your bowel could be bad for your health. i would use a modified inflatable butplugg connected to a pissing condom with a tube. When urinating the butplug should expand, or not?

[cdinbonds]

I seriously doubt that a normal urine stream would be able to inflate the buttplug, even if it was outside the body. Inside, with the rectal walls pushing in on it, even less likely. Try inflating the plug with your lungs by blowing into the inflation tube. I'm guessing you won't be able to do it, but if you can, you'll discover that the pressure required is way more than a urine stream can develop. Let us know what you find out, I'm sure there are lot's of people that want to know if this can work.