Relatively clean will do. She wants to be dry, not spotless.

"You're not thinking about it right." It isn't a rebuke, just calmly factual while she rubs her hair with the towel. "This isn't something I was born with, it isn't what I am. It's just something I've got, it's a weapon." Rachel thinks about this for a moment and shrugs, puts her attention back on the towel. "If someone breaks your knife, it breaks the knife - it doesn't break you. That's a pretty crappy metaphor, but it's basically it."