This phrase uses a non-existent form of genitalia as a vehicle of hyperbole to convey the idea that something is insanely and impossibly small and tight.
I can't get any stock tips from these rich bastards -- their lips are tighter than mosquitopussy!
A phrase used to define something that is outstandingly magnificent or "cool", obviously surpassing the extremity of the situation in which the words "tight" or "tite" are used.
Although the tightness of a twat may very it is assumed that we are speaking of virgin twat unless, of course, you change the context by adding the name of someone who is not assumed to have a tight twat. (See example 3)
When using this phrase all sexual connotations should be ignored and the phrase should be used to express ones awe in something rather then being regarded as "dirty" or "perverted".
"Holy balls! The new album by Breathe Carolina is tighter than twats!"
Did you see that?! It was tighter than twats when Becky punched Jessica in the face, knocking her front tooth out!
Well that was about as tight as Tanya's twat. We all know she's a whore.
Something that is extremely tight. Usually referring to nuts and bolts on a car.
Most commonly used in a mechanics garage and is the result of many skinned knuckles.