Ten'oh Haruka and Kaioh Michiru
Soulmates
Ten'oh Haruka and Kaioh Michiru are by far my personal favorites of the 'lovers' of BSSM. They posses a strange elegance and maturity over the other couples of the series. They have an undying bond that is never truly fulfilled in the Anime or the Manga.
We never know much about this strange pair. They're histories are revealed briefly in a BSSMS episode but we only learn about how Haruka came to know Michiru and became a sailor senshi. This is enough to teach a person what type on bond these two have. Sailorneptune begs Haruka to not pick up her henshin stick. Sailorneptune didn't want they same fate to happen to Haruka, but in true fashion Haruka rebels from Michiru's directions and transforms anyway.
They're mission, when we first meet them, is to obtain the three talisman, at any cost. Over the episodes we see that this means that they would even sacrifice each other for these talisman. Haruka, the tomboy of the pair, follows the path more strictly. Haruka's seemingly last words to Michiru are rather cold and cocky, saying that she knows not to save Michiru. And she stays true to that, even when Michiru goes through quiet a bit of pain for Haruka's sake.
Though they're relationship seems cold, Haruka eventually realizes what Michiru means to her and they grow closer then anyone else. They exchange soft touches and small glances that say millions. One cannot discribe the love that these two, soulmates, fell for each other.