I figure that Kogasa had to fly up to get the pagoda down from the tree to begin with, so she was just coming back down.
Naaaaz?Explosions are scary.TrembleShudderSafety first!!There, see? Sure enough, it's perfectly safe.Plop...PoofExplosions are scary.ShrsshWell, you're always so cheeky, Naz-chan...but Miss Toramaru would never do something like that..... Wait, whoa! Naz-chan, where'd you go!?Naz-chan... you're quick to escape, as usual.