I don’t think there’s all that much to it, honestly, but I’m definitely not one for interpreting visual imagery (or really lyrical imagery, for that matter).
What I got out of it was that their true selves are represented as those we see at the beginning, in the black clothes. As they sing the lyrics that question who they truly are, they look as if they’re positively devouring each other. It’s a very intense image that emphasizes the verses, such as,
“I’m grotesque, can you love me? To be honest, you want to cry, don’t you?
Do you hold my pass for living today? It’s me, why don’t you kill me?”
After the first segment, they split off into groups of two - the representations of their true selves, and the representations of their polite selves. They then present the same intensity as they sing the verses at their other sides, which, I suppose, represents inner turmoil.
As for the rabbit, it dons a mixture of both white and black clothing, toting a gavel to make clear that it is a sort of judge. I would guess that this image would suggest that it is there to decide which side will prevail - the grotesque inner self or the polite facade.
As I said before, there really isn’t much to it, just like pretty much all of Namie’s PVs. It’s just there provide an aesthetic and emphasize the tone and theme of the song.
I hope that helped you, though, nonnie!