The term "a bar of soap" is an expression used to describe an individual who is very fickle; you can never keep hold of them for very long without them slipping out of your hands. Typically given for a person who is overtly avoidant.
Henry's always changing his mind last minute, he's such a bar of soap.
john: why is there a giant health bar in the sky other john: sub to headshot craft
other john: hey johns can you talk a little quieter? I'm trying to watch hentai