YES! Thanks for your help! It's really Rainer and Uschi. I noticed something familiar with that man. I was drawn to the woman for other reasons...
Anyway, I saw some photos of both Rainer and Uschi long ago, so thanks for the reminder.
I agree the person in the back is very feminine, so it's probably a girl. I didn't notice that hidden person.... hmmm..... could it be Peter... ?
I wonder if there are other photos from this party...