The Beach Episode. It's a lot more difficult to watch a second time, because you know that Bravo is having fun with the kids knowing full well that he's going to have to kill Kazuki at the end of the day.
Fridge Brilliance
A homunculus's insatiable desire to devour humans is later explained to originate with their desire to regain their humanity. This is why Papillon doesn't need to eat people; he hated being an ordinary human and embraced the change.
