光榮（Koei）在創業初期確實曾經與「成人遊戲」有過一段如今較少被官方主動提及的歷史，這段經歷主要發生在1980年代初期的日本個人電腦遊戲黎明期。當時日本的PC遊戲市場尚未成熟，開發成本高、玩家族群有限，許多小型工作室為快速回收成本，會選擇開發帶有成人題材的作品，因為這類遊戲在當時的銷量相對穩定，也較容易引起話題。光榮正是在這樣的產業背景下誕生，而非一開始就以歷史模擬或策略遊戲為發展方向。

1982年推出的《Night Life》被視為光榮的第一款商業作品，同時也是其最具代表性的成人題材遊戲之一。這款作品並非單純的感官刺激，而是結合當時相對罕見的「成人向人生模擬」概念，玩家在遊戲中經營角色的生活、人際關係與親密互動。雖然畫面與表現受限於當年的硬體條件，但在玩法結構上已可看出光榮對「數值管理」與「模擬系統」的濃厚興趣，這也被後來不少研究者視為其日後專精模擬遊戲的重要雛形。

隨後在1983年與1984年，光榮又陸續推出《団地妻の誘惑》（常被譯為〈住宅區人妻的誘惑〉）以及《オランダ妻は電気ウナギの夢を見るか？》（〈荷蘭老婆會夢見電鰻嗎？〉）。這些作品延續成人題材的路線，帶有濃厚的昭和時代社會氣氛與當時流行的獵奇命名風格。值得注意的是，這些遊戲在表面上是情色作品，但實際遊戲結構仍以事件觸發、狀態管理與選擇分歧為核心，顯示光榮在技術與設計層面已逐漸累積製作複雜系統的能力。

真正的轉捩點出現在光榮創辦人襟川陽一與襟川惠子逐漸意識到，成人遊戲雖能短期獲利，但難以建立長期品牌價值，也不利於公司規模化發展。於是光榮在 1980 年代中後期果斷轉型，將重心移往歷史題材與策略模擬遊戲，最終誕生《信長之野望》與《三國志》系列。這些作品不但成功開創日本歷史模擬遊戲的黃金時代，也徹底重塑光榮的企業形象，使其從邊緣市場的小型工作室，躍升為具有高度文化辨識度的主流遊戲公司。

也正因如此，光榮後來對早期成人遊戲作品的態度相對低調，這些遊戲幾乎不會出現在官方年表、紀念企劃或宣傳資料中，常被玩家戲稱為「黑歷史」。然而在產業史角度來看，這段經歷並非單純的污點，而是光榮在技術、人力與資金尚未成熟時的現實選擇，也是日本PC遊戲發展史的一部分。

進入現代，光榮已成為「光榮特庫摩（Koei Tecmo）」集團的一員，主力作品集中於歷史策略、動作遊戲與大型 IP，例如《真三國無雙》、《戰國無雙》、《仁王》等。雖然旗下如《死或生》系列因角色設計較為性感而廣為人知，但這類作品仍屬於主流商業遊戲範疇，並非成人遊戲。同時，公司對角色形象與IP管理極為嚴格，對未經授權、涉及成人內容的同人作品採取強硬態度，這也反映出其早已與早期成人遊戲時代徹底切割，轉向以品牌價值與長期經營為核心的企業路線。

總體而言，光榮早期的十八禁遊戲並非偶然，而是時代與市場條件下的產物。這段歷史雖然與今日光榮的形象形成強烈反差，卻也為其後來在模擬與策略遊戲領域的成功，奠定重要的技術與設計基礎。

Koei did, in fact, release several adult (18+) games in its early days during the early 1980s, a chapter of its history that the company itself rarely brings up today. This period coincided with the infancy of the Japanese personal computer game market, when development costs were high and the player base was small. For many fledgling studios, adult-themed games offered a relatively reliable way to recoup costs quickly and attract attention. Koei emerged in this industry environment and did not originally position itself as a developer of historical simulation or strategy games.

Released in 1982, Night Life is generally regarded as Koei’s first commercial title and one of its most representative adult-themed works. Rather than focusing purely on erotic imagery, the game incorporated what was then a relatively uncommon concept: an adult-oriented life simulation. Players managed a character’s daily life, relationships, and intimate interactions. Although its visuals and presentation were constrained by the hardware of the time, the underlying structure already showed Koei’s strong interest in numerical systems and simulation mechanics. In hindsight, many commentators see this as an early prototype of the design philosophy that would later define Koei’s simulation games.

In 1983 and 1984, Koei followed up with titles such as Danchi-zuma no Yūwaku (often translated as The Temptation of the Apartment Wife) and Oranda-zuma wa Denki Unagi no Yume o Miru ka? (Does the Dutch Wife Dream of Electric Eels?). These games continued along the adult-content route and reflected the distinctive social atmosphere and provocative naming trends of the Shōwa era. Despite their surface-level erotic themes, the core gameplay still revolved around event triggers, state management, and branching choices, indicating that Koei was steadily building expertise in creating more complex systems.

The real turning point came when Koei’s founders, Yoichi and Keiko Erikawa, realized that while adult games could generate short-term profits, they were ill-suited for building long-term brand value or scaling the company. In the latter half of the 1980s, Koei decisively shifted its focus toward historical themes and strategy simulation games. This transition eventually led to the creation of landmark series such as Nobunaga’s Ambition and Romance of the Three Kingdoms. These titles not only ushered in a golden age of historical simulation games in Japan but also completely reshaped Koei’s corporate image, transforming it from a marginal PC game studio into a mainstream developer with a strong cultural identity.

As a result, Koei has tended to downplay its early adult games, which rarely appear in official timelines, anniversary projects, or promotional materials. Among players, these works are often jokingly referred to as the company’s “dark history.” From an industry-history perspective, however, this phase is less a stain than a reflection of the realities faced by early developers, and it forms part of the broader history of Japanese PC gaming.

In the modern era, Koei—now part of Koei Tecmo—has firmly established itself around historical strategy, action titles, and large-scale intellectual properties such as Dynasty Warriors, Samurai Warriors, and Nioh. While franchises like Dead or Alive are well known for their sexually appealing character designs, they remain firmly within the realm of mainstream commercial games rather than adult titles. At the same time, the company strictly protects its IP, taking a hard line against unauthorized adult fan works to preserve character and brand integrity. This stance underscores how completely Koei has distanced itself from its early adult-game period, embracing instead a business model centered on long-term brand value and sustainable development.

Overall, Koei’s early involvement with adult games was not accidental but a product of its time and market conditions. Although this chapter contrasts sharply with the company’s modern image, it also laid important technical and design foundations that later supported Koei’s success in simulation and strategy gaming.