Anyway, let's catch up with the kids. Before that brief cut to the teachers, Rain and Chanel did just walk into prom together. Today we see them catch up with (most of) their group, and everyone reacts perhaps the way you'd expect.
Ana's "pretty, little head" comment was previously used a few pages ago. And she's using it here the same way she used it there: saying something silly to derail potentially dangerous questions from people not necessarily in the know. http://rain.thecomicseries.com/comics/1126/
Given that RSVP forms the seniors had to fill out spelled out that you could only bring a "guest" of the opposite sex, (see http://rain.thecomicseries.com/comics/879/ ) I'd say his confusion about them coming to prom together is understandable.
Given his particular insecurities I doubt that he's unfamiliar with the idea that two girls could be a couple.
Me: WHAT?!? The title of the page isn't actually used in the dialogue? That doesn't happen very often, I must have missed it!
Ana: Don't you worry your pretty little head over it!
Ky and Drew approached the group a couple pages ago... ^^;
http://rain.thecomicseries.com/comics/1127
Just asking for clarification
Given his particular insecurities I doubt that he's unfamiliar with the idea that two girls could be a couple.
Ana: Don't you worry your pretty little head over it!