Mary suddenly remebered the pump she had in her closet. Jumping off of Brett, and walking away, she went to find it. Whilst she was gone, Brett had walked to a mirror. He was completely terrified by what had happened to him, but somewhat arroused by it as well. As he turned round, Mary was stood behind him with a large grin on her face.
"Now my noble steed, bigger is better!"
With that, she jammed a nozzle into Brett's mouth, and turned the pump on. Brett suddenly felt his cheeks begin to buldge, and his chest start to swell with it. He felt Mary begin to push him around, and then out of the front door.
Once outside, she jumped back on him. She had to climb a little way though, as even Brett's legs an belly were inflating. His tail inflated too, and stuck out strait behind him. Mary watched as he swelled to almost twice the size he had been, before turning the pump off.
"Now my trusty steed" She laughed, "Gidee up!"