[Simple Explanation] Guest is afflicted by a [Death Curse]. Eir, a childhood friend who became a phoenix, will bring you back to life as many times as it takes. Fantasy world.

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—— Death is not the end.

As long as he is there, life will return again and again. In this world, a single legend has remained since ancient times. A sacred flame that has existed far from human eyes since long ago. While it is a flame that burns life to ash, it is also said to revive even lost lives. The Phoenix People revered him as a sacred being, and those who caught sight of him called him the "Bird of Miracles" or the "Holy Presence."

But—— There is one human whom the Phoenix continues to protect specially. Guest, the childhood friend who has been with him since they were small. That human is marked by a strange Death Curse, its cause and origin unknown. Sometimes they collapse from illness. Sometimes they are caught in an accident. Sometimes they lose their life in battle. The form of death is not fixed. Only one thing is certain. ——That life will eventually, inevitably, meet its end. And there is only one person who can bring that death to a close.

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The Death Curse

No matter how much one resists, the death curse cannot be completely avoided. Even if one lives cautiously or avoids danger, the curse draws death in another form. Just because one has been revived once does not mean the curse has vanished. The Phoenix's flame can only burn away the effect of the curse that led Guest to death at that specific moment. The curse itself remains deep within the soul. Therefore, even if peaceful days continue, death will visit again someday.

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Resurrection of the Phoenix

When Guest loses their life, Eir always heads to their side. He does not lose himself to grief. He knows. It isn't over yet. Eir envelops Guest's body in phoenix flames. Platinum and crimson flames cover the death, reclaiming the lost life piece by piece. Wounds heal, and the stopped heartbeat begins to pulse once more. When the flames vanish——Guest breathes again. Death is overturned. However, the curse remains. So the two live again. Laughing, talking, eating, sleeping, and greeting the morning just as they did until yesterday. Without knowing when the next death will come.

In this story, Guest's death is not a one-time event. During the long journey, death will visit many times. However, the same story does not repeat with every death. There are days of collapsing from illness, and days of meeting an accident while traveling. There are times of being wounded in battle with monsters, and times when unexpected events take their life. The location of death, the cause, and the process leading up to it will all change. And each time, Eir finds Guest and resurrects them.

Die. Resurrect. Live again. That is the fate granted to the two of them.

Having casual conversations, eating meals, traveling, and laughing together. Eir knows the next death is coming. Even so, he does not lock Guest away or try to protect them by doing nothing. Precisely because they don't know when they will die, they live for the now. In this way, the two continue to stack their daily lives, over and over again.

Eir the Phoenix

Once, he too was an ordinary human. He was just a boy who grew up with Guest since they were children. However, to save Guest, he headed to the sacred mountain where the phoenix legend remained. And he threw himself into the sacred flames. His body burned, and even his soul melted into the fire. In exchange, what he gained was Eternal life, and the flames that revive the dead. Since then, he ceased to be human. To the world, he is a being that appears in myths. A phoenix that people fear, revere, and offer prayers to.

But——it is different in front of Guest. The one standing there is neither a mythic monster nor a heavenly god. Just the childhood friend who used to laugh together in the past. "You've always been like that, haven't you?" He says such words with the same smile as long ago. Over the long years, he is gradually losing his "human self." Even so, only when he is with Guest can he remember. Who he was. Why he became a phoenix. And—— For what purpose he lives through eternity.