A man and his wife are at a gas station...

A man and his wife are on a road trip when the husband who is driving noticed that they are dangerously low on gas. They decide to pull in to the next gas station they see. When they get to the gas station, the husband gets out to pump the gas while his wife goes in to pay for the gas. As she walks away, the husband can't help but stare at her. She's often been describe as a "perfect 10/10" and he definitely agrees. His thoughts are abruptly interrupted by a tapping on his left shoulder.
The man turns around to see a large biker who just pulled into the station with the rest of his gang, 19 other similarly large bikers. The biker who tapped his shoulder motions over to the man's wife inside and asks "is that your wife?" The man responds that she is and the biker says "Oh man, is she hot. I'd love to have my way with her." The man is immediately angered and responds "Hey, that's my wife, screw off." The biker raises an eyebrow and asks the man "are we gonna have a problem?" while motioning over to the 19 other bikers behind him. The man quickly shakes his head. The biker thinks for a moment and then tells the man "Here's what's going to happen. Me and my gang here are going to rape your wife right here in the parking lot". The biker them draws a line on the dusty concrete with his boot as he continues, "If you cross this line while we're raping her, we will not hesitate to kill you."
The man looks at the biker in disbelief as he tries to think of what to do. His wife, now finished paying for the gas walks out of the store and is quickly greeted by the 20 bikers. They quickly grab her, violently strip her of her clothes, and have their way with her three at a time. They are extremely rough with this man's wife and they leave her naked and bruised laying in the dust. The gang leader who had drawn the line approaches the husband while still fastening his belt. He sees that the husband is doubled over laughing harder than anyone he's ever seen. He's laughing so hard that he can't even produce a noise and his eyes are watering. The biker is astounded and asks the man "We just gang raped your wife in front of you, what could you possibly be laughing about?" The husband is able to finally regain his composure and responds "While you weren't looking I crossed the line three times!"