The youkai people are one of the two dominant ethnic groups in Kozan, besides the humanoids. Youkai-borns make up for one-third of Kozan’s population. To get an understanding on what makes a person a youkai-born, we need to talk about genetics.
Youkai-borns, by definition, are humanoids who are of spiritual descent. Although the origin of youkai are typically supernatural creatures originating from the Shinto religion, this typically concerns the youkai who have humanoid appearances. In the Drillimation Danmaku Universe, some people called themselves youkai-borns partly because they hailed their heritage to spiritual descent.
In order for a person to be declared a youkai-born, they must have 67% of youkai blood in their genes. Any person with between 33 – 67% of youkai blood are half-youkai, half-humanoid. Any person who has less than 33% of youkai blood are generally regular humanoids, though they may still be called youkai-borns, even though they really aren’t.
What caused the explosion of the youkai-born population was during the Edo period in Kozan, during the time that the great deity Flandre was around, many people converted themselves to youkai-borns to avoid the wraith of Flandre. Flandre’s followers committed murder in hopes of sparking a race war between humanoids and youkai-borns, and that’s how the entire conflict started.
In order to ensure that youkai-borns had an overwhelming majority of youkai blood, many youkai-borns chose to marry youkai-borns and increase the amount of youkai blood in their descendants. Should a youkai-born choose to marry a humanoid, their descendants will be half-youkai. If two half-youkai parents have children, their offspring will also be half-youkai.
History of Youkai-borns within Kozanese Royal Families
The history of youkai blood being present in Kozanese royal bloodlines dates back to the Edo period and the founding of the Federal Kingdom of Eastern Kozan, People’s Kingdom of Central Kozan, and the Democratic Kingdom of Western Kozan. King Rinnosuke was the consort of all those three kingdoms on the Kozanese continent. He was half-youkai, and we don’t know who the humanoid and youkai-born parents were.
When King Rinnosuke and Queen Marisa had their one and only child, he ended up being a humanoid with 25% youkai blood. Crown Prince Kichou missed that 33% mark by eight percentage points. Same thing happened with Empress Kaguya having her one and only daughter, the Crown Princess Tewi II. Kaguya was a Lunarian, and they ultimately declared her half-youkai.
Queen Yukari’s daughter, Crown Princess Maribel, is in fact, a youkai-born with 25% humanoid blood, the rest is all youkai. Furthermore, both the Eastern and Western Kozanese Royal Families were predominantly humanoid and youkai-born respectively. When the People’s Kingdom of Central Kozan and Democratic Kingdom of Western Kozan folded into the Federal Kingdom of Kozan after the Meiji Restoration unified the continent into one country and became daimyo families for their respective provinces, they continued this trend as if they still ruled their respective countries.
Furthermore, in 1982, youkai-born Kanata Kobayakawa broke this tradition by being the first youkai-born to marry into the Kozanese Royal Family when she married Prince Soujirou the same year. The following year they had their one and only daughter, the half-youkai Crown Princess Konata of Kozan. A lot of people were upset about the marriage, and was the reason why a Soviet spy assassinated Queen Consort Kanata in the first place.
Where may humanoids and youkai-borns go in the first place? Well, only time may tell.