You don't have to give a crap about dancing ... to give a crap about Rumer Willis emerging as a major piece on "Dancing with the Stars" -- although you'd have to watch the damn show to know that. 

As we've said ... she doesn't need the Mirrorball Trophy (but she'll probably get it) -- Rumer's already won the Now Everyone Knows I Have a Bangin' Body award.

Exhibit A: this outfit with the neckline down to her belly button, and the leg slit up to her ... ya know.

Kudos to Bruce Willis and Demi Moore too ... for the Best Damn Genes award.