Act 0: Birth of Tuxedo Mask

What if Usagi was never Mamoru Chiba's true love? What if Usagi was only Sailor Moon while someone else was the reincarnation of Princess Serenity? What conflicts would that bring to the sailor scouts, but most of all, for Usagi and Mamoru and you?
(Mamoru Chiba x Reader x OC)
(Onesided! Usagi Tsukino)
Disclaimer: I do not own Sailor Moon Crystal or its characters.