Regionally, its just a yearly thing. It falls on the same Day as Gliedinspektionstag in School.
Gliedinspektionstag is only in anti-trans-communities in the US I thought? Or... did you visit a Catholic school?
It's bad german for: we have to make a shit. Probably meaning: i have to take a shit. The others say: let's look at the shit, followed by: that's a good shit