Hoga Yasahiro, who wished for death as he lost all interest in life, comes to realize he's immortal as he fails his suicide attempt.
Isozaki Izumi who is so afraid of losing those around him, has a complicated past that led him to lead a simple life with simple goals as he struggles with attachment.
As events escalate, Yasahiro and Izumi find out that they share nothing but immortality; making their partnership very hard.
With no clue of how it happened, they start investigating and asking questions for very different reasons. Yasahiro wants to end it, and Izumi wants to make use of it.
They start sharing memories of dying, a heavy secret with traumatic effects, traumatic enough to unite them in the face of whatever that comes, as it won't be as bad as death itself, or so they thought..
A story of two immortals struggling to live many lives in a world that has more mysteries than they could ever imagine.