You can tell Asaki's having fun singing the song; at the end, after one last shout of "O-KOOOOOO-MEEEEEEEEE!", he delivers the following spoken line:
"Ahaha...okome oishii!" (Rice is delicious!)
The fact that Asaki and 96 don't appear in the event, presumably due to being Reclusive Artists; instead, they have two stand-ins pose for them. Asaki's in particular is a Caucasian male who looks nothing like him.