1. The eyebrows come together and curve up at the inside.
2. The eyes become big and childlike
3. The lips and sometimes the chin shake.
Number three is what actually constitutes wibbling.
Billy: Uh...I dunno...
Billy: Oh, Sarah! Of course I will!
George: "What is 2 plus 2?"
Blackadder: "Wibble, Wibble."
Blackadder, trying to prove he is mad, in his bunker, with underpants on his head and a pendil up each nostril
After making love three or four times in a session wibbling may include a component of lethargy ending in sleep.
This seldom happens during one night stands.