When you strap a dildo on your forehead and then fuck your girl with it, like a unicorn on amphetamines
by bussdat November 09, 2010
When one straps a dildo on their head and then proceeds to fuck their partner in the ass, head first with the strap on, resembling a unicorn.
Last night I was at a magic show and somebody asked the magician to see a trick, he then put a dildo on his head and performed the screwnicorn trick
by Bullfrawg February 17, 2015