When you have a threesum with two guys and one girl in which one of the male members ejaculates on the other's big toe, and he proceeds to put his toe in the girl's vag. Then the one who put his toe in makes a wish that she doesn't get pregnant.
Jeff: dude, I heard you had a threesum last night
Nate: yeah man, it was me, Richard and Catie- we tried a Scottish Genie
Jeff: ah man, i hope your wish comes true
Nate: yeah man, it was me, Richard and Catie- we tried a Scottish Genie
Jeff: ah man, i hope your wish comes true
by Johnny Derp March 5, 2011