High‑school student Kei—alongside at least forty‑six others—receives immortality as the most shocking twist imaginable.
Unfortunately, this gift does not elevate him to hero status. To both the public and authorities, he is seen as a rare subject destined for capture and transfer to researchers who will conduct life‑altering experiments—an immortal half‑human forced to endure countless deaths for mankind"s gain. And the relentless pursuit of scientific progress drives their actions.