Many ancient nations in this world practiced sacrificial burial.
As an ancient superpower, the Kakin Kingdom was naturally among the foremost practitioners.
Since antiquity, it had maintained a special sacrificial burial custom known as the "posthumous consort."
On the surface, a posthumous consort was someone sent to the underworld to accompany a deceased prince.
In reality, the custom existed to prevent princes who had failed to become king from turning into vengeful spirits after death and threatening the new king and the nation.
It was a means of control that extended even beyond death.
This also showed how seriously this ancient superpower took "preserving sovereign power," giving rise to many almost pathological practices.
Under the enduring influence of this "ancient national culture," people both above and below the throne cultivated retainers willing to die.
And when these "death-sworn retainers" were combined with Nen, curse-type Nen abilities emerged.
The Kakin Kingdom's second prince had a unit of death-sworn retainers whose sole purpose from birth was to serve as curses.
After awakening their Nen and selecting a curse target, they would carry the target's name, photograph, clothing, and even bodily material such as hair or flakes of skin.
Then they would grip a small knife and stare at the target's photograph every day, gradually building an overwhelming resolve to curse the target to death.
Once the time was ripe, they would burn everything associated with the target to ashes before activating their ability, then boil those ashes into a brew and drink it all.
Since these curse-type abilities typically required "death" to activate, the ideal method was for the caster to commit suicide directly in front of the target.
That way, the caster's post-mortem cursed Nen would immediately attach itself to the target and drain their energy...
While forcing the target into