Glaswegian Unicorn
A sexual position where people engage in ménage à trois but the centre person wears a dildo strapped on their forehead and gets down on all fours. All people have had plentiful amounts of scotch and one person performs vaginal or anal sex behind the 'unicorn' while another literally rides the unicorn's horn.
"I hear that Tom, Jessica and Beth got really fucked up at that party, apparently they were doing a Glaswegian Unicorn in front of everybody."