The skinny one.

You take up too much room. You are so heavy and solid and real, and you don't want to be. You wish you could be like a child's balloon at a fair, drifting, attached only be a thin string. And you wish the child would let you slip from their hands, and you'd float off into the atmosphere.

Even if everyone would shout below for you to come back, you want to let go. And be free.