Hah, I could almost see this happening... As a punishment for Rei being a bitch to Usagi or something. The Outers are VERY protective. However, the sword is supposed to be gold, not red.
I could see this happening, but with a different logic to my thought process. Uranus and Neptune are already lesbians, Mars is a closet submissive/masochist, and Pluto is a voyeur *after all, all she ever does is chill outside the timestream, watching everything...*