Soap

Is soap self cleaning?  For instance, if you visit someone's house and go to shower or wash your hands and there is clearly a used bar of soap, does it make you nervous to use it?  Will you get germs from whomever used it first?  And what if there is a hair on it?  Do you dare touch the hair to get it off or do you tip-toe around the hair and hold it under running water hoping the hair will slide off?  What part of the body did that hair come from?  And who's body did it come from?  And did the previous user of the soap lather bubbles on their hands and then distribute it to their body parts, or did they vigorously rub that exact bar on their unmentionables?  So many questions.  Am I the only one who gets a little squirmish from a used bar of soap?  I don't wear other people's underwear, so why should we share soap?  But that brings me back to my original question.  Is soap self-cleaning?  Cuz if it is then the problem isn't the soap.  The problem is that I need therapy.