Spoiler for Thoughts and speculations...:
I find it really amusing that it is again Origami and Tohka who display unusual acuity when it comes to Shidou. Granted - bar Kotori - they have spent the most time alongside Shidou. Some really nice illustrations this volume as well - we get to see Kaguya and Yuzuru in casual clothes for the first time (nice going with the chuuni outfit, Kaguya
). Also, Yoshino in that witch cosplay (HNNNGGGG~).
...The revelation about Natsumi has to be a shock for most people. I bet they were expecting something... more to their tastes.
Nonetheless, I'm expecting a lot of hijinks in the next volume. Turning the cast into 9 year-olds has two implications: either they revert purely physically or both their memories and appearance regress. If it's the latter, there's more potential for comedic mess-ups and a little bit of an insight to their childhood memories. If it's the former there's still potential for entertainment, but little else.
Anyway, I look forward to digging up more information for the latest volume... sometimes you have to look for it to affirm some of the spoilers.