Final panel, I believe it's Teetoku saying her "Nanojya" verbal tick except she's slurring her words. I've seen this in other works when I translated touhou stuff. A very common one for example was Sakuya often slurring her "Ojou-sama" whenever she was shocked or nose bleeding over Remilia.
Kuu's bubble is her misunderstanding Teetoku, at least that's how I view the final panel.
Mmmm, whatcha say, Mmmm, that you only meant well? Well, of course you did Mmmm, whatcha say (whatcha say) Mmmm, that it's all for the best? Of course it is
W-what!? You wish a fight!!Kuu, a good morning to you~Now, now.It's Teetoku-chan.to-Whaa!?It's because today, I'm an Amatsu-chan exclusive, you see~Ama~vu.Nattou?
Fermented soybeansNaa!?