A "desk dump" is the act of jumping onto the desk of a co-worker or manager you hate and doing a poo in the middle of their desk to express how much you dislike them. A similar concept to leaving a bag of dog poo on someone's door step.

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.