..head.
Rob grinned excitedly, setting the belly button to change the size of his head. he set the size to 'grow', and then, he pressed his belly button.
immediately, his head expanded in size a little.
"Amazing, it really works." he said. "Now for some real fun."
He pressed his belly button again, and his head grew to double it's size. It felt heavier, but, he was impressed by it.
"Wow." he said. "They used to call me 'big-headed' in college, but now it's true."
This gave a new meaning to the term 'big-headed'.
He looked like a bobblehead doll.
Feeling reckless, Rob pressed his belly button one last time, and held it down. Rapidly, his head grew and grew until it was as big as the door.
It was so heavy, it pulled him to the floor with it's weight.
Rob quickly set his belly button to shrink, making sure it still focused on only his feet, and pressed it and held it down. Immediately, his head shrunk down till his head was normal sized.
"Phew." he said. "I'm never making my head bigger (B)EVER(/B) again."