But will Kanna still act like a little girl? Regardless of her ability to alter her appearance, I wonder if she'd mentally mature at a reasonable rate.
I wonder is Kanna might find some way to either turn Saikawa into a dragon or at least make her live and age at a similar pace as hers (or maybe turn herself into a human, though that'd considerably reduce her life-span).
I mean, considering the whole magic, might still be some way.
if that's true, Tooru wouldn't be so freak out when she's thinking Kobayashi might die someday (it shows in manga, I forgot what chapter)
it means that dragon cant give their immortality to human.
The death of the human and survive of the dragon over the time is their fate, and the dragons are well aware of this. Nothing can stop this to happen, so they'll simply live each days to their fullest. That's why Kanna act something a little pushy with Saikawa.