Aww, why'd you stop?"
2. Implying that you wish to have sex with the person your 'unce' is directed at. Often, drool is also released from the mouth while saying it with this meaning.
Teacher: Here are your papers everyone, Joe, good job!
Joe: YES! Unce unce unce unce -walks around in circles, bobbing head back and forth-
Teacher: . . .
Joe: Man, I am so happy that I aced that essay----
Sue: -whips hair around-
Joe: Unce! -drools-
Sue: GASP -slaps Joe-
Joe: Oww. My cheek...
Bob: Sue again?
Joe: Yeah...but she has such a hot unce!
Taylor: A hundred percent, yo.
Claire: UNCE! All over that shiiiit.
2) Claire: Look at that hot piece of booty.