I can say that, in the great majority of the Chinese faces I see everyday, the upward tilt is hardly noticeable, unless emphasized by makeup (or crow's feet).
I tend to associate a strong upward tilt with the 'new' D&D elves more than with Eastern Asian people ;-)

I love the wonder on her face, and the first part of the sketch too, although in my mind's eye the people in the poems aren't that strongly Japanese (that's a personal thing, though).