John and Mary had been high school sweethearts, but they never had sex. "We'll have to wait until we are married," she told him.
So he waits.
They are engaged three years, and finally the big day rolls around. On their wedding night, Mary comes out of the bathroom, and says "I have some bad news. I have my period, and I don't want our first time to be all bloody!"
John says, "You're kidding!"
Mary says, "We'll just have to wait a bit longer."
Mary goes to sleep, and wakes up at 3:00 am to get a drink. On her way back to bed, she notices Johnny wide awake staring at the ceiling.
"There's no use John," she said, "You might as well go to sleep."
"I would, except my dick's so hard there's not enough skin left to close my eyes!"