What is Bullet Train?
1.
When a man slides his penis up and down the outer labia(lips) of a very wet vagina while erect. Creating a fast sliding action up and down similar to a bullet train on rails.
I was with my girlfriend last night and she was so wet I ran a bullet train over her.
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2.
It is when you fart in the intake vent of a CPAP machine.(The machine the people with sleep apnea use)and it gets sucked in and blown into there nose through the mask.
"I stopped by my buddiers house and he was still sleeping, so sent him the BULLET TRAIN to wake him up"
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