back before the use of tampons, women used cloths to hold their excrement after their period. So Bomba is referring to their Bum, and Clat is Cloth. Bum Cloth, a rude sayin in countries where this term is used.
other
It literally means butt cloth but its used to swear at people or because something fucked up etc.

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.