how long?

"hey, please let me ask you something."
"alright. you can ask me anything."
"how long?"
"what's long?"
"how long? c'mon, you are an intellectual."
"um, don't you think that's a bit personal?"
"no no, silly. how long will this last?"
"oh. i.. don't know. how long was the last?"
"but i don't understand, whatever do you mean?"
"oh i see. well all i know is that this is clean."
"is it clean enough for a sheen?"
"dear baby, it's too good to wean."