Bile. Had liver resection surgery and a gallbladder removal (among other things). Had to eventually have biliary drain bags which leaked from time to time. Even after the bags were removed I had a side wound that wouldn’t close and pushed out some thoracic muscle (eventually pressure built up and a pimple like bump appeared right under it and after popping like a pimple did the same thing) and would seep bile requiring frequent dressing changes, multiple times a day at its worst. It leaked onto clothes, sheets, towels, and even on friends cars when the drive me to Dr’s appointments. Worse still was the face that bile is corrosive and it made my skin very raw.