First of all...I can't figure out how to spell these things. Some folks spell it C-ton like you did and others seton like my doc did. If the medical world can't agree on how to spell it, we'll never get people to spell crohns correctly
I had a seton in a rectal fistula. It was in for quite a long time as the infection and size was quite large. After almost twelve months, the seton came out on it's own. I didn't even really feel it. There was a little blood, but I had little muscle involvement so there was very little pain. My surgeon said that the blood was a good sign when I called their office---basically it was in the final stages of healing. I swear that within a day after it fell out, I had no symptoms of ever having had a fistula. Thank goodness I am one of the lucky ones...I hope you have as positive an experience.
Dx'd '90 (emergency rupture), symptoms ignored long before that, '03 fistulas and bad flagyl reactions, B12 weekly, Pentasa [until I surrender to the bigger meds]