It's a real song! samuraiblues mentioned Kanjani8 in a comment yesterday and kawaiis found the song on YouTube. It's so cute and Orihime and reminds me of Don Kanonji's BOHAHAHAHAHAHA:
(eta: the song was removed on YouTube but I found it here
I'm fixated with the Kubo's poetry as always. The title of the last chapter was "A Day without Melodies" and with that retro-Bleach chapter cover, I'm reminded of the Ichigo who used to have a guitar in his room (it's not there now--the wall posters are gone too) and was often pictured wearing headphones. Orihime has a theme song for her life but she tells her friends (with some concern) that she's only "humming" it now. Tatsuki speculates that this is because Orihime's grown up, so what's going on here? Is the music changing?
It's like old style Bleach, but it's not the same old song.