Threadborn follows Yono Kazeshima, a boy who dies in the most undignified way possible and wakes in another world with a goddess, a strange mark, and a weapon that absolutely should not be a tennis racket. In Asteria, every bond is a Thread, every broken promise leaves a scar, and something ancient is pressing against a sealed door beneath the world. When Yono runs toward a scream in the burning city of Lumera, he finds Liri, a child caught in the shadow of monsters, and begins pulling people into his life one impossible rescue at a time. But the mark on his palm is not a blessing. It is a seal. And the thing behind the Covenant Door already knows his name.