The joke, I think, is that Byakuren, with her mighty buff magic, can keep pace with the train. That's what's got Mamizou freaked out. She knew Nue's pal was fast, but not THIS fast.
I think Nue+Mamizou are disguising themselves as humans (no wings on Nue, human form for Mamizou) and Byakuren is kind of blowing their cover; hence their reactions. Nue looks like a embarrassed kid trying to ignore her mom's over the top waving good-bye.
I think Nue+Mamizou are disguising themselves as humans (no wings on Nue, human form for Mamizou) and Byakuren is kind of blowing their cover; hence their reactions. Nue looks like a embarrassed kid trying to ignore her mom's over the top waving good-bye.
That's it. The two are visiting the outside world. Though that handkerchief waving and face really amuse me.
But yeah, maybe the picture quality isn't satisfying enough.