I think he is talking about the meaning as we have in the use of the name Jan ("To shake Jan's hand").
BTW IIRC the name Peter comes from the greek word for rock. Kinda applicable with the slang meaning of the word 
Well, boys have a penchant for such things. The other day I was thinking of the times in grade school when I learned many of them, we made up some of our own, etc. Good fun.
You should always get nervous when there's a bunch of naked germans with cameras around glass topped tables.
I wish I didn't know that. 
From what I've seen, anything sexual involving german folk one might be wary of. They have the japs beat.
As for the display itself, I don't 'mix drinks'.