>>71332535She wants to avoid the embarrassment of screwing up/not knowing the lyrics, so she screws up on purpose. Like, if I'm gonna die, it will be on my terms. Yes, it's a karaoke, they're there just to have fun, but autism is too strong, please be kind. I thought she grew out of this, but apparently not. Maybe being will other girls together brought up the debut Mori back to the surface.
Also, it was pretty funny how you can practically hear Kiara giving her the look or lightly punching her shoulder so she would stop doing dumb shit like that. Near the end of mogu mogu you can even hear her going "sorry, sorry" and singing normally when she tried to pull that silly voice again, no doubt because of someone's death stare.
