When a man and woman have sex with the man sitting up at the top of the stairs while the woman rides him, during the session, they slide down the steps.
When a man has sex with a woman at the top of a stairway "doggy style," he has her facing the stairs and holding onto the top step. When about to about to come to climax, the man kicks out the woman's arms out from under her and rides her down the stairs bobsled style. The vibrations from the stairs cause an unparalleled orgasmic experience.
Warning: this sex act may cause damage to said woman's face.
4 guys in line. Guy in the back of the line inserts a buttplug into his own ass and his thumb into the ass of the guy in front of him whilst masturbating. That guy does the same to the gentleman in front of him, and so on down the line. The guy in front of the line is in charge of the speed and tenacity of the group. He may also call out cadences. "Feel the rhythm, feel the rhyme. Let's all get off, it's bobsled time!"
The act of inserting ones johnson into the vagina,while forcing her onto her back in order to ride her down a staircase, hence the bobsled.
Bob- Dude did you notice those marks on your staircase Jeffey- Yeah whats up with that?
Bob- Me and your mom tried the slovakian bobsled last night, shit got out of hand
Jeffey- Dammit dude again?
A sexual act in where a man is engaging a woman doggy style next to a flight of stairs and then pushes her down the stairs and rides her the whole way.
Bob:Hey man, what did you do last night?
John:Oh nothing much, i just pulled the Russian Bobsled on Jen.
Bob:Nice, hopefully it didn't bruise her knees too bad.