Paragon of Sin

The Dark Yin Palace was a Gold-tier force that limited its recruitment requirements to females, preferably young and impressionable. But like most sects, they were divided into a series of complex networks of clans, interests, and status. Not without that standard complexity, the Dark Yin Palace was not only composed of female cultivators; they only recruited females.

The distinction was clear, as males born from members of the sect or married into it via the clans, later joining due to that special connection, were also a part of the Dark Yin Palace. 

The sect itself established its foundation on its unique cultivation called the Dark Yin Spirit Method, designed to weaponize the Primal Yin quintessential energies and mould a Spirit of Cultivation with its qualities. During the Qi Condensation Realm's Infused Spirituality Phase, the female cultivator would merge their Primal Yin quintessence with their Spirit of Cultivation, establishing a Yin Natal Soul.

The best effects of such a method was an amplified level of bodily talent, increasing the body's refinement speed of various resources, especially those yin-attributed, and an auric charm. As the body is constantly refined by yin energies, generated and produced in excess by the Yin Natal Soul, the cultivators were typically gorgeous women with tantalizing charm, alluring auras, flawless skin, and shapely features.

While subjective in belief, and many would disagree, there was a rumor spreading that this resulted in women reaching an 'ideal' female state. They were actively 'refining' their bodies to be ideal in attracting mates, and this was utterly natural. This, however, didn't cause many of them to look like clones of each other, but most would find distinct similarities in some features, like limpid and alluring eyes or smooth, blemish-less natural skin.

Through this uniquely risk-free method, previously limited only to those with special Yin-type physiques, refined alchemical products, or certain Evil Methods, the Dark Yin Palace produced some of the greatest female cultivators amongst the Gold-tier forces. However, this method was not without its flaws. 

While most of these flaws were speculated by experts, many unable to be truly verified unless by the cultivator themselves, the apparent flaws were publicly known. The most obvious of them all were that the Primal Yin Source of females had extracted their purest, essential energies, their Yin Natal Soul acting as a substitute. 

This led to them being always at risk of losing their entire cultivation alongside their chastity. The struggle to remain pure when your body was a literal treasure in the cultivation world was extremely difficult, especially since cultivators often hit a plateau and were unable to ascend further. If passing one's bloodline meant losing it all, it simply wasn't worth it. Yet being unable to pass your bloodline after your death was extremely depressing, especially if you've reached great heights in your cultivation.

It had to be stated that females, all those within Mortal Limits, at some point in their lives would lose their ability to reproduce, and likely far before they reach the limits of their cultivation. This was a matter of realm, not strength. 

The clock of postmenopausal was not halted, just pushed further back. Those at the Foundation Establishment Realm lost their child-bearing abilities roughly the same age as non-cultivators, 40 to 50 on average. While those within the Qi Condensation Realm were extended, reaching 120 to 140 on average. Those at the Astral Core Realm were 600 to 700 on average. 

It was said those at the Mystic Ascendant Realm, those who exceed Mortal Limits, have broken away from this restriction, but it was increasingly difficult to verify as those at this level were rumored to have extreme difficulty in birthing children. But only those at that level knew the truth.

After a certain point, regardless of a mortal female's bodily strength, their bodies would be subjected to a natural law, and they'll lose their qualifications to have children. This deadline meant those who sought to cultivate this method would lose over 50% of their potential cultivation time. While the benefits can multiply a cultivator's refinement speed, the fact that this occurred was harsh.

This flaw was later focused upon by the might of alchemists, medicinal sages, scholars of cultivation, and high-level cultivators urgently. It became a puzzle to be solved, and almost everyone was incentivized to do so. After all, dual cultivation had far, far greater long term benefits, not just an explosive burst. The combined might of focused attention was unreal, and a solution was soon reached. 

As a result, almost with exceedingly unimaginable swiftness, an alteration of the Dark Yin Spirit Method was discovered, and it was called the Linked Duality Spiritual Spell. The female cultivator could, by this Spiritual Spell, link a male cultivator's yang aura with their yin aura, and interactions such as dual cultivation became possible without the female cultivator losing everything. Of course, it wasn't that simple either.

This was heralded as a great advancement for a while until the irremovable flaws of the spell itself was revealed. One of the major, yet not even the worst, was that dual cultivation was entirely one-sided. While the female could, in theory, have sexual relations, they still could not have children due to the imbalance of yin & yang energies within their own bodies, while the male in question would also be unable to extract anything from the dual cultivation session, yet each time, the female would extract their vital essence and cultivation base. This was an unintentional consequence of the link, and unable to be stopped by either party.

The original name for the Dark Yin Spirit Method was lost with time, and renamed due to this horrifying development, earning its 'Dark' title. Yet due to the combined effort of many powers, few were willing to classify it as an Evil Method..

This led to everyone slowly being dejected and taking the small, short-lived win. But the Dark Yin Palace's female cultivators were still desirable. After all, that link spell required two willing parties.

Therefore, the Dark Yin Palace had quite a reputation amongst the various forces. To have children, a female cultivator had to lose everything before they fully reached the limits of their cultivation, including the very things that made them desired: their beauty and talent. But it wasn't only for that reason…

-----

It's been several weeks since the recruitment of the Gold-tier and Silver-tier forces had ended. Many of those selected had entered forces, joining the cultivation society of the Aeternal Sky Starfield.

Amongst these youths selected, within the Dark Yin Palace's planet Immortal Yin, there was a female figure dressed in black and dark blue tightly-fitted robes that accentuated every exceptional feature, every delicate curve, and every alluring angle of her body. She was currently situated in the Dark Yin Palace's Pure Yin Palace Hall, one of the twelve Palace Halls of the Dark Yin Palace. 

While the Dark Yin Palace was renowned for the Dark Yin Spirit Method, it wasn't actually defined by that single method, merely what it built its reputation and foundation upon. It actually had twelve varied Yin-based cultivation methods, and some even allowed for children to be born, yet its not nearly as world-defying as the Dark Yin Spirit Method that could amplify talent and beauty to unreal levels.

Each method was defined by a Palace Hall, with the Pure Yin Palace Hall placed for members who cultivated the Pure Yin Convergence Method. The method was far more gentle, less extreme, and placed importance on using one's Primal Yin Energies to slowly refine materials and their cultivation base, focusing on Purists' Ways, such as Tuo Bihan's path. They boasted having great cultivation foundations, while not sacrificing their ability to comprehend Intent.

The female figure was Na Xinyi! She was in her own cultivation room, and was automatically elevated to being a Core Disciple after her Four-Point Yin Physique was discovered. After a heavy, heated set of arguments between the upper-echelon over which Palace Hall she'll be inducted into, she chose the Pure Yin Palace Hall and its Pure Yin Convergence Method.

This was to be expected as she had Four Primal Yins, so this would greatly affect her cultivation speed and foundation. At the moment, she was inspecting the contents of her ring as she focused her entire attention on the Neo-Eclipse Dawn Pill and its unbelievable description. 

When she asked her assigned instructor about the possibility of forging a Domain Seed prior to reaching the Realm World Phase, she was rebuked for such impossible thinking, that not even the strongest geniuses can accomplish that feat. Told that she should focus on realistic goals, yet looking at this ninth-grade product that her fiancé, the brilliant Wei Wuyin, had made for her left her unsure. 

As she finally decided to consume the pill, outside of planet Immortal Yin, Wu Yu was attempting to slip through the planetary defenses. However, when he reached the borders of the planet's atmosphere, the ring of grey mist that shrouded the planet, he was met with a wall.

After steadily approaching, the mist started to rile up and became flowing like water. It arrived before him almost instantaneously, threatening to engulf him whole, like a hungry python. Wu Yu softly snorted and retreated with a single step backwards, vanishing and reappearing a hundred kilometers away. The grey mist coiled and hissed, but had lost its target, returning to its original state after an artificial spiritual sense swept fifty kilometers around the planet.

Wu Yu's regal countenance formed a slight frown, "From that little Realmlord I captured, this should be a Gold-tier force which should only have a few failed Ascended, yet its planetary array was definitely established by multiple experts at my level. You really can't rely on information from mortals. How troublesome." After making this disgruntled remark, he contemplated a way to enter. 

As he was about to make another attempt, his expression abruptly changed.

"May I ask which Venerable is visiting my Dark Yin Palace? To whom do I owe this honor?"