The ending to this series, ever since the day the site went live, was announced to be performed by PASSPO☆, an apparently flight-attendant themed group of singers I've never heard of. ("Don't call me a waitress!") The OP is by Yuki Kanno.
So, I wanted to know how PASSPO☆ sounded, to get an idea of their music before the show went live. I know AKB and I know MomoClo, but I don't know these girls. So here's a short version of their latest single. (Not the anime's ending. That's "Truly".)
I can get behind this. Also, if it isn't clear, music is a vital part of a series' identity for me.