The Commonwealth of Englia began to be threatened by a humanoid monster called Alice decades ago. Alice generated bookworms, harmful creatures that feed on books, and unleash a rotten nightmare when they devour the souls in a book. Our hero, Mr. X, conceals the fact he is a minor so he can become a bounty hunter. He was assigned to work alongside No. 9, a cold and arrogant hunter who likes to wear a gas mask.
Their chaotic adventure starts with an ally-adversary relationship: the reckless and the ruthless. As the story unfolds, other characters join in the risky undertaking: the AI caterpillar system that can detect Alice's whereabouts, the mission team named "Sista" that assists Alice's cruelty, and the "March Hare'' killer that has been raised by Sista.
There is also the Cheshire Cat who spreads legends and anecdotes of Alice and brings trouble to the hunters from time to time. The hunters follow a trail of breadcrumbs until the duo finally comes to the "Countess" who lives on the artificial island in the sky, and in the end, discovers the record of everything.
A young and cheerful hunter who prefers firepower to complicated tactics. He relies entirely on his reckless intuition, but because he has a kind heart and is gifted at caring for others, he wins everyone's tolerance.
No. 9 is a real name and not a code name. He is a caring young man who prefers to complete his task with minimal gunfire, and who never removes his gas mask. He rarely communicates with others.