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.

The Price of Harmony

The squad briefing room felt cramped with the entire 373 present - plus a few medical staff. Everyone sat uncomfortably straight in their chairs as the chief physician delivered his report. His terminal projected a series of neural activity readings that painted their mission's toll in cold data that most of them could understand.

"Navigator Naia's harmonic output exceeded safe thresholds multiple times the last mission. This is in addition to similar incidents many times this past half year. The strain on her vocal cords is severe."

The doctor's fingers highlighted specific spikes in the historical data. Clusters of red marked moments of particularly concerning power usage that was a bit more technical, but made Naia wince in immediate understanding. All Navigators study their own data and compare it to the general baseline.

'Frequent seven percent over. A height of plus fifty three this time? By the timeline, that was when I-'

Chapter 62 - Renewal Protocols