This is a sexual activity where a male buys a Shamrock Shake from McDonalds, which is basically a McFlurry which is defined by McTwist and the Shamrock Shake being a neon green color is defined by the Neon in the title. Then the male puts his penis inside of the Shamrock Shake for as long as he likes and then slowly pulls it out leaving neon Shamrock Shake residue on his penis. He then performs intercourse until the girl screams because she is bleeding. The color of blood, red, is the Stoplight color telling you to stop.
Last night we performed The Screaming Neon Stoplight McTwist in my car, it was messy.
by Brant Sucker February 21, 2010