[@KatherinWinter]

It was said weeks ago that they were childhood frenemies, which is why they mess with each other without remorse on the way to class. Kari understands the clock directions because it's relative to her, not relative to David. "Forward" is noon, 12:00. You can give directions to a blind person this way and lead them; people just use a clock because it's easier to visualize than "273° clockwise."