This is what really happens when a bunch of girls use the bathroom together. They all take their pants off and stack one on top each other on the toilet. Then then go pee and it becomes like a urine champagne tower. The champagne tower is also known as "stacking".

The phenomenon of having to come out as bisexual to the same person/people repeatedly because they assumed or hoped that your sexuality was a "phase." Refers less to the holiday and more to the 1993 Bill Murray comedy film in which the main character experiences the same day over and over.