You wake up sleepily to see a slightly different glow on the stomach walls of your mistress. Assuming it's morning you wait afraid to desturb her. But then you remember that your movements are a gentle massage inside of her so you give a big streatch.
"Took you loon enough sleepy head now let's get ready for our day!" she gets up and heads staight for the shower. She was probably already naked. As she turns the water on her belly gets even warmer and you hear and feel the water hit against her stomach as she bathes. All of a sudden she remembers the deal. "Oh my gosh! I forgot to let you out"