Dragon's Heritage was, at its core, merely a magical mechanism. Back in Akiyama Noriko's homeland, it would probably be called a ritual formula.
The purpose of this magical mechanism was to have those affected by it plunder life force and transmit it to the Cherry Dragon, the source of the magic, to heal its wounds. This could happen through direct killing or through slowly draining the vitality of those nearby. Killing needed no further explanation, while those whose life force was gradually drained would develop an illness known as Dragon Cough due to their loss of vitality.
At first, it manifested like a persistent cold, with incessant coughing. In the end, they would die once their life force had been completely drained. Naturally, the Cherry Dragon took the lion's share of that life force, which was transmitted to it for healing. But for the sake of sustainability, it left some behind for the afflicted, allowing them to revive through Resurrection.
Thus, the Ashina Clan, a small nation with a sparse population that had always wanted to cultivate immortal soldiers, and The Hand, which served life itself and pursued immortality, had both desperately sought to fully understand it.
Yet from the moment the Ashina Clan and The Hand discovered this phenomenon, they had conducted relentless research. In the end, however, they achieved only superficial results, and this situation continued until Dragon's Heritage vanished.
So they believed that someone had wielded a divine blade called the Undying Blade and destroyed this magical mechanism. In truth, though, the Cherry Dragon had merely entered hibernation and later departed once its wounds healed. Dragon's Heritage, which had been used for healing, naturally lost its value as well.
But in reality, this magical mechanism had continued to be passed down through the bloodline formed by the