In the Manga Rei and Minako are best friends and somepeople think they even have a relationship like that of Haruka and Michiru. in one story Minako is jelous of Rei because of the school she goes to and all the attention she gets from boys, so she uses her cresent moon thingy(I've never read Sailor V so I don't know what it's called.) and transforms herself in to a T. A. student. After getting in trouble a few times she tells Rei that she was wrong and that they are nothing alike.  Minako runs away and Rei chases her. In the Process Rei becomes contolled by a spirit and begins kissing all the girl in school. Minako see's this and imediately transforms. Rei tries to kiss her and Minako ends up using one of Rei's ofudas to banish the spirit. So obviosly they were close enough for Rei to have tought her that anti-evil spell. Another noteworthy comic is in the Sailor Stars story when Rei and Mina are ontop of a building and the Three Lights show up and Rei and Minako put thier arms around eachother and Rei says "We don't need any men." Than they die together. They don't ahve much interaction in the anime though, and Serena is Rei's best friend. I think that they are so close becuse they are so diffren. They draw from eachother what they don't have in themselves. Many also think that they are the stongest of the inner senshi, because of an episode where Tuxedo Mask was talking to Pluto, Uranus ans Neptune and Uranus says that not even Venus or Mars could handle the new danger.
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