diddling her twat
fingering, or playing with a girls vagina.
Oh, he's probably diddling her twat.
diddle her twat
To touch a vagina in anyway. Ususally takes place while drunk and or stoned. Most diddlers wigle the middle three fingers of their hand around the clit unless you've got a reall saggy one then you can diddle away all over the place.
Guy 1 - I really want to go meet the girl over there.
Gyu 2 - You pussy, just go diddle her twat.
Gyu 2 - You pussy, just go diddle her twat.