Lesson 3: When using a human shield, grab a fat guy.
Kallen's... poorly-planned... kidnapping/assassination attempt on Lulu. It hadn't occurred to her that if you sneak up on someone in the shower, they will, in fact, be naked. Doubles as Fridge Brilliance when you realize that this is a quite visceral example of just how much the resistance groups in Japan needed Zero's genius to stand a chance.
Kallen:Why are you naked?! Lelouch fought his initial response that generally, people got naked to take a shower.
One of the history info dumps ends up being a cram guide for an AP test.