There's a pic where they show all of Sazanami's seasonal art over the past four years, and how it shows growth from being an apparent 12-year-old to a 16-year-old.
Asagumo wants to have Kai-2 soon toooooooo!!Yamagumo, seee?
She likes small ones toooo♪Hurraaaaay♪T-Thanks.Congratulations on Kai-2, Michishio-nee!
Hurraaaaay♪You're sure looking cool there!
And it feels like you've grown somehow...The two of them want to get stronger too, eh?
Small?flat...Michishio Kai-2!!
I'll show you the power of the stronger me!!