K.
His sage advice.
"Don't worry," K flashed a reassuring smile. "Jesse doesn't even know when my birthday is, so I don't see how familiarity is going to be such a problem in the near future." She air-quoted her fingers on familiarity.
Jesse pressed his lips into a straight line, and has come to the realization that he in fact doesn't know a lot of trivial things about K - her age, her birthday, her real name.
"You don't want to tell me those, anyway," he croaked and got all defensive. He sounded butt-hurt and a little annoyed. "What's the point?"