I was sort of surprised to see new characters introduced in this manga. I'm pleased - one of the things I like best about Souichiro Yamamoto is the seemingly endless interesting characters he creates and the skill with which he has them interact (and in fact that's exactly why Kunoichi Tsubaki is my favorite of his series). But I guess I had just come to assume that he wasni going to do that with this one - that he had made a deliberate choice to stick with just the main three plus a handful of team members no matter what. But here they are, and they're already terrific.
And on another note, I suspect that Nagisa and Himemiya (and maybe even the entire club) already know about Ichinose's birthday, and she's about to have her heart warmed.