A man and a woman, who have never met before, but who are both married to other people, found themselves assigned to the same sleeping room on a totally booked transcontinental train.
Though initially embarrassed and uneasy over sharing a room, they were both very tired and fell asleep quickly - he in the upper bunk and she in the lower.
At around 1:00 AM, the man leaned over and gently woke the woman saying, "Ma'am, I'm sorry to bother you, but would you be willing to reach into the closet to get me a second blanket? I'm awfully cold."
"I have a better idea", she replied. "Just for tonight, let's pretend that we're married.
"Wow, that's a great idea!", he exclaimed.
"Good", she replied. "Get your own blanket!"
After a moment of silence, he farted.