A husband and a wife made a code for sex so that the kids won't hear. The code was typewriter.
One day the dad told his child, "Go tell mom I need the typewriter tonight." The little girl told her mom. Then ran back to the dad and said, "Mommy said the typewriter is busy tonight and tomorrow."
The next week the mom went to the dad and said, "Want the typewriter?" The dad shook his head and said, "No I found another one. A newer one."