Lorelai: I need hand soap.
Luke: What?
Lorelai: Oh, she got ink all over her hands from the fingerprinting and I'm out of soap.
Luke: I have soap.
Lorelai: Maybe she needs special soap. Is there special soap? Is it special ink? It must be special ink, right?
Luke: I don't-
Lorelai: I mean, of course. They're not going to use normal ink for fingerprinting, it's supposed to brand you and humiliate you. Normal ink wouldn't humiliate you, unless you're Rory and your mother has no soap.