Seraphelki

In a galaxy ravaged by war and haunted by the ever-expanding Dead Zones, Naia is a skilled Harmony Navigator - a person of extraordinary powers that can temporarily stabilize paths through them. Thus she was trained and recruited into the branch of the military known as Vanguard Operations.
She finds her romance - a welcome stabilizing factor in her life - thrown into turmoil when the enigmatic and powerful soldier, Theia, joins her squad. It would be clear to anyone that the two women looked very much alike… and it was long clear to Naia that this woman was the one she was always meant to replace in Evander’s heart.
Bound by duty, Naia must navigate not only the treacherous reality-bending terrain of the Dead Zones but also the growing tension and unspoken desires within their team. As her squad leader Evander's attention slips ever more towards the alluring and unpredictable Theia, the Navigator grapples with feelings of jealousy, insecurity, and a growing sense of isolation.
Love & Duty - Or Duty & Sacrifice? A balance that the three can live with is sought.
Will she be able to maintain her focus and fulfill her vital role in the war effort, or will the discord fomenting within their squad consume them all? Naia must confront the rising tide of chaos, both within herself and slowly building in the world around her… ultimately discovering the true price of harmony.
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Romance-Drama with a Science-Fantasy setting.
Messy Triangle - yes. An Omni-Directional one?
At times, but it's not poly.
Some FxM R-18/Smut... 
Interspersed tastefully and plot progressively.
--In this author's opinion, anyway.
* Eventual Les/Yuri/FxF scenes, yes. *
You're Welcome.
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If you like your love stories poking you in the feels in the middle of fantastical settings, check out my other works too!
It's kind of what I do.

Chapter 61 -