I got one:
We will use Harold and Maude in this one also....and just as old.
It is bedtime and the two meet in the hallway.
Harold: "Fuck you, Maudie"
Maude: "Fuck You Harold"
..and they quietly go to their separate bedrooms.
Next night.
Harold sees Maude in the hallway again. "Fuck You Maudie...and she responds in kind....they go to bed.
Next night.
They meet in the hallway again...and Harold says "Fuck You Maudie"
Maudie responds:..."Harold!"...
"Yes, Maudie?"
She looks perplexed..." I just don't understand what these young folks see what is so great about oral sex"