Once when my bf and I were babysitting his dad's dog we came home to find 3 such piles of what I then assumed was diarrhea under our bed. It was as you described, brown, consistency of choco pudding, and mucousy. But no smell. Well no poopy smell anyways.... Turns out when Dudley had broken out of the babygate he had gotten into some chocolate and that made him puke like that. He was fine the next day.