Sharing a bathroom can be disgusting because people are vile. The worst roommates leave traces of themselves behind and force others to clean after them. It’s disgusting because nobody wants to find hairs or dried vomit all of the time.
ThisIsNotAWar wrote: “She pooped in the shower. Multiple times. She puked on the floor and left it there all weekend while I was away. Oddly, what I found to be her worst offense was when I walked in on her washing her dishes in the sink with my toothbrush.”