Dantalian no Shoka Wiki
Dalian (right) confronts Mithril (left).

Japanese Name


Romanized Name



Phantom Thief (怪盗 Kaitō)

Phantom Book Thief (幻書泥棒 Gensho Dorobō)

Doctor (先生 Sensei)

Yuna Foster Kosaka (ユナ・フォスター・コウサカ Yuna Fosutā Kōsaka)

Harban (ハーバン Hāban)

Police Officer (巡査 Junsa)


Chapter 5 (light novel 4)

Voice actor




For the light novel chapter titled "Phantom Book Thief", see Chapter 5 (light novel 4).

Mithril, also known as Phantom Book Thief or Phantom Thief, is the user of the Faceless Book. Grosseteste tries to capture her. Marchbanks is her henchman. She disguised herself as Yuna, Elisha’s personal doctor, and as Harban, a police officer. She interacted with Hal and Flamberge during the events of the Phantom Book Thief story, and with Hugh and Dalian during the events of the Vignette of Eternal Twilight story.


Mithril stole several Phantom Books from different places in the past.[1][2] As part of her plans, sometimes she sends letters to the police, warning them that she will steal something. Many times, she escapes the crime scene using the Faceless Book to disguise herself as police officer. Inspector Grosseteste is tasked to catch her. He and other policemen are punished every time she escapes. When she's not disguised, she assumes the form of a beautiful Asian woman in white coat. However, after using the Faceless Book so much, she's not sure about her original appearance.[2]

A few days before the main events of Phantom Book Thief, she sent a warning letter to the police and newspapers, telling everyone that she would steal a valuable Phantom Book from Ben Arkin. Using the Faceless Book to disguise herself, Mithril was hired as Elisha’s personal doctor under the name Yuna Foster Kosaka. Mithril is after the Phantom Books protected by Hildegard inside the basement of the Reizl Castle.[1] Mithril knows about the existence of the Dantalian's Bookshelf protected by Hugh and Dalian and of the Book Burning Officers.[1][2] Mithril wants to steal the Phantom Books inside the Labyrinth Library. It seems like she has a good reason to steal Phantom Books, possibly associated with a difficult part of her past.[2]

She has a knife made of mithril, a translucent, phantom metal which shouldn’t exist, stronger than steel, with a gleam of silver, used to cast out evil. The handle has a pattern depicting a black griffin, the symbol adopted by the Phantom Book Thief.[1] Detective Marchbanks is Mithril's henchman.[2]


Mithril is resourceful and sly. The manipulative thief unceremoniously uses everyone, including the police, to achieve her goals. She sends letters to the authorities in order to create an opportunity to disguise herself as a police officer and escape from the crime scene. She’s very confident in her abilities, mocking her opponents. She’s a proud, immodest person. Mithril is a master of disguise, fooling everyone while pretending to be someone else. Only Hal and Hugh are able to learn about her schemes. Even then, Mithril bursts out laughing, acting boastful. She's very skillful while handling her silver knife.[1][2]

Mithril usually prepares her disguises beforehand. After all, her Faceless Book cannot copy complex mechanisms, such as the camera of a photojournalist. Mithril is a thief, but she doesn't take people's lives. She laments when her plans end with casualties. She tenses when Dalian asks why she's after Phantom Books, as if she can barely hold back her tears.[2]

Yuna, her alter ego, is focused on caring for Elisha’s health. She prepares tea of medicinal herbs for Elisha, treating her affectionately, promising to cure her, worrying about her. She’s grateful that Hal saved the young girl. Yuna has a mischievous and mockingly side, which reflects Mithril’s original personality.[1]

Mithril also disguises herself as Harban, a police officer who's on vacation. In disguise, she manages to completely fool Inspector Grosseteste. She acts as an aggressive, threatening and impatient man. Grosseteste is always apologizing for the policeman's rude behavior. As Harban, she pretends to suspect others of being the Phantom Book Thief. Hugh especially gets under the skin of the fake Harban. Mithril also disguises herself as Shura, mimicking the photojournalist's behavior with perfection, to the point of fooling Dalian.[2]


Disguised as Yuna or not disguised at all, she assumes the appearance of a young woman of about 25 years old, with oriental features, wearing a white coat. She has a long, black hair tied in a ponytail.[1][2] She has vacant eyes. In Vignette of Eternal Twilight, she affirms that she's not sure about her original look.[2]

When Mithril pretends to be the Scarlet Robe, she covers herself with a red garment which appears to be soaked in blood. She also disguises herself as a young detective, Grosseteste’s subordinate, using a cheap coat. Mithril reveals her identity as the Phantom Book Thief while wearing the Faceless Book, which is a mask with no features.[1]

Disguised as Harban, a police officer, she looks like a man of almost two meters in height, with broad shoulders and a square body, wearing a business suit. She also pretends to be a wooden guignol doll summoned by the Marquise. In such state, she appears to be a three-meter grim reaper, with a black cloak and a sharp scythe. Mithril also pretended to be the photojournalist Shura, although she had no time to obtain a camera.[2]


Phantom Book Thief[]

A few days before the main events of Phantom Book Thief, Mithril sent a warning letter to the police and newspapers, saying that she would steal a valuable Phantom Book from Ben Arkin. Mithril stole many Phantom Books in the past. Flamberge provokes Hal, saying that he was stupid for believing the headlines. She asks Hal if he became Mithril’s fan, or if he wants to catch the thief to gain fame.

The Reizl Castle is filled with policemen trying to catch Mithril, led by inspector Grosseteste. Hal and Flamberge are examining the magical barrier cast on the ramparts of the castle, when they see the Scarlet Robe running on the walls, carrying an unconscious young girl. The mysterious figure has inhuman abilities. He’s as fast as Hal’s motorcycle. The Scarlet Robe easily jumps to the ground, as if ignoring gravity. Hal manages to block his path. The kidnapper wasn’t out of breath, even after the high-speed pursuit. He lays Elisha on the ground and assumes a fighting stance. Hal attacks the Scarlet Robe with his staff. The latter avoids the blow, jumping on Hal’s shoulders. The Scarlet Robe jumps again, pushing Hal’s shoulders, as if mocking the Book Burning Officer. The kidnapper disappears in the forest nearby.

Hal and Flamberge carry Elisha back to the Reizl Castle. They notice that Elisha was kidnapped from her bedroom, at the top of a three-story bedroom. Ben, Elisha’s father, calls for Yuna, who checks the unconscious young girl’s pulse and heart rate, while also looking external wounds. Yuna sighs in relief, ensuring Ben that his daughter only needs a restful sleep. Grosseteste introduces Yuna as Elisha’s personal doctor. Yuna heard about Book Burning Officers from and old patient. She didn’t believe that someone like Hal really existed. Yuna explains to Ben that a Book Burning Officer is someone with the task of destroying Phantom Books.

Elisha is awake in her bedroom, drinking a tea of medicinal herbs. Yuna welcomes Hal and thanks him for saving Elisha. The doctor raises her hand to introduce herself, but Hal ignores her gesture. However, she acts like a child, pouting and grabbing his hand by force. Yuna approaches Elisha, putting a hand on her back while she’s coughing. The young girl’s health was worsening over the past six months. With a gentle smile, Yuna promises to cure Elisha. The latter explains that she was resting when the Scarlet Robe showed up. Elisha had noticed the smell of medicinal herbs before passing out.

Elisha gets out of bed to guide Hal and Flamberge to the library, as a way to retribute their efforts. Yuna shrugs, as if to say that it would be useless to stop the young girl. After the massacre caused by the Scarlet Robe in the library, everyone goes to Ben’s study to discuss the matter. It's clear that the interests of Mithril and the Scarlet Robe intersected at the Reizl Castle. Hal believes that the Scarlet Robe is Elisha’s doppelgänger. Yuna wonders if that’s the reason for Elisha’s poor health. Hal explains that someone inside the castle is possessing Elisha by using a Phantom Book. The young girl, at the guest room, screams right after waking up. Someone had used a knife to hang a bloody dress on the wall. Grosseteste notices a black griffin on the handle of the knife, the symbol of the Phantom Book Thief.

Hal, Flamberge, Ben and the policemen go to the basement to find Ben's late younger sister Hildegard, the Scarlet Robe. Meanwhile, Yuna should have been with Elisha at the young girl’s bedroom, taking care of her. A young detective, Grosseteste’s subordinate, struggles with nausea and backs away after seeing the bone-strewn floor of the basement. Later, when Hildegard is about to kill everyone, the young detective reappears, stealing the Decorative Plywood of Merneith from Hildegard’s hands. The man smiles mischievously, provoking the witch. A familiar summoned by Hildegard jumps to rip the man’s throat. He destroys the creature with a wave of his knife made of mithril. The young detective puts on a faceless mask, revealing himself as the Phantom Book Thief. Mithril dodges Hildegard’s familiars, showing unbelievable dexterity. Hal knows that he’s using a Phantom Book. Mithril throws the Decorative Plywood of Merneith to Hal. The Book Burning Officer destroys Hildegard’s soul and Phantom Book using his staff. Mithril disappears amidst the chaos. Grosseteste’s subordinate was later found unconscious in the castle's pantry. The subordinate said that, after seeing the bones in the basement, he hid himself and then suddenly lost consciousness.

Hal and Flamberge find Yuna inside the basement, after the skeletons were collected by the police. She was distracted, looking at an old portrait. Hal knows that Mithril hasn’t come for the Decorative Plywood of Merneith. Hal explains that the Scarlet Robe was trying to possess Elisha. The witch had no reason to kidnap the young girl. Furthermore, the powerful magician didn’t need to resort to medicinal herbs for the abduction. Mithril had disguised himself as the Scarlet Robe for Elisha’s kidnaping. Mithril planned to have Elisha saved by Hal. That way, Hal would be invited to the Reizl Castle, overcoming the magical barrier cast around the property. Mithril had also sent a warning letter, telling everyone she would steal a Phantom Book from Ben, in order to attract the police and a Book Burning Officer. After all, Mithril needed help to open the basement and to destroy Hildegard, since the witch was protecting the Phantom Books hidden behind the portrait. Yuna bursts out laughing, revealing herself as Mithril.

The doctor removes a faceless mask from her breast pocket and puts it on. It’s the Faceless Book, a Phantom Book that gives its user supernatural power, and the ability to assume thousands of different forms. Hal wants to burn the Phantom Book. He attacks with his staff, but Mithril easily avoids, jumping over Hal. Mithril affirms that she’s not interested in the Phantom Books inside the basement. She doesn’t want to fight. Mithril tells Hal to not burn himself with his own fire. She jumps once again, disappearing. Later, Elisha tells Hal that she knew that Yuna and Mithril were the same person. Elisha wants to thank the doctor for keeping her promise. Elisha seems healthier, now that her doppelgänger was gone.[1]

Vignette of Eternal Twilight[]

Hugh and Dalian drive to the Asquith castle. Harban, a police officer, stops them for an interrogation. Shura pushes him away, interrupting him. As a suspect, Shura can't enter the castle. Harban grabs her shoulder, irritated due to the interruption. Hugh refuses to answer Harban's questions without a proper introduction from the police officer. A throbbing vein is clearly visible in Harban's temple. The tense moment ends when Inspector Grosseteste shows up, recognizing Hugh.

Although the inspector knows Hugh as the grandson of Wesley Disward, Harban still suspects of him. Grosseteste apologizes for Harban's rudeness. It's revealed that the Marquise of Asquith is offering a huge reward for the guest who finds the Vignette of Eternal Twilight sealed somewhere inside the Asquith castle. Shura affirms that she was stopped because the police don't want to give her the opportunity to find the Phantom Book. Harban growls at her, enraged. According to Grosseteste, the police is after Mithril. The Phantom Book Thief sent a letter to the police, warning them that she will steal a book inside the Asquith castle.

At the library, Harban talks with Grosseteste and Hugh. Harban knows that people around the Vignette of Eternal Twilight die under strange circumstances. Grosseteste is frustrated because it would be difficult to find the Phantom Book Thief, a master of disguise, among so many guests. Mithril had escaped crime scenes many times while disguised as a policeman. According to Harban, the police is punished every time Mithril escapes. Grosseteste tells Harban to be quiet. The latter continues to suspect of Hugh, Dalian and Shura. The police officer is ready to arrest Hugh if necessary.

It seems like many guests are interested in the reward for finding the Vignette of Eternal Twilight. Harban crosses his arm and examines the people around. He recognizes Dawson, a investor on the verge of bankruptcy. Although people are searching for it, it doesn't look like the Marquise really wants the Phantom Book. After all, she allows the searches only once a year, and she never hires specialists to find the valuable item. When dinner is to be served, the guests leave the library. Many seem to be uncomfortable in company of the formidable Harban. Now that the library is empty, Hugh opens a secret passage behind a bookshelf. Harban's jaw drops to the floor.

Hugh and the others enter the secret tunnel. They find a thick metal door guarding the Vignette of Eternal Twilight. Detective Marchbanks was standing by the door, passionately embracing Evelyn, one of the Marquise's maid. Harban watches as Marchbanks and Dawson fight to grab the Phantom Book first. The police officer is not interested in separate them. Dawson opens the Phantom Book. Harban notices that the Phantom Book doesn't look valuable. The Phantom Book disappears soon after. Evelyn stares at the ceiling, frightened. Feeling the danger, Hugh and the others run out of the secret room. Dalian falls, but Harban carries her out of the room by the head, as if grabbing a rugby ball. The ceiling collapses soon after, crushing Dawson to death.

They walk to the garden, where they feel a different atmosphere. Their watches have stopped. The other guests have disappeared. The front gate of the fortress vanished. Marchbanks suggests looking for Evelyn to interrogate her. Harban grabs him by the collar, lifting him off the ground. The policeman tells the detective to find the maid immediately. Inside the castle, they find Evelyn and the Marquise, who looks as young as her daughter Lyfia. The Marquise summons grim reaper dolls to kill them. Harban draws his weapon. Evelyn begs for mercy, but she's impaled by the scythe of a grim reaper. Harban tries to tackle the creature, but the swing of the scythe makes him fly away. Harban shoots at the monsters. He tells Hugh and the others to run while the enemies are distracted.

A damaged doll was at the feet of a beautiful Asian woman. She hears the sound of rusty gears. Mithril checks her pocket watch. She knows that she's inside the world created by the Vignette of Eternal Twilight. A grim reaper doll jumps out of the darkness to kill the thief with a sharp scythe. Mithril pushes a silver knife against the monster's chest. Someone in the distance recognizes the phantom metal used to destroy evil. Mithril smiles confidently. Everything went a little out of plan, but she knows that the other guests will handle the situation. She impatiently brushes her bangs off her face. She hears a loud laughter.

Hugh and the others run to the library. It's revealed that the Marquise uses the Vignette of Eternal Twilight to gain eternal youth. For that, she has to kill her guests. The grim reapers block the exits. Shura's camera is broken during the confrontation. She was about to be killed by one of the creatures, but the grim reaper freezes. The monster is destroyed by another doll. The savior turns into Harban. Soon after, he turns into a beautiful woman. Her scythe becomes a silver knife. She easily defeats the grim reapers. Mithril removes her mask. The Phantom Book Thief had been disguised as a police officer the whole time. Shura is surprised to learn that Mithril is a woman. However, the thief is not sure about her own true face. Dalian recognizes the Faceless Book, a Phantom Book in the form of a mask that allows the reader to obtain others' strength and appearance.

Mithril had disguised herself as a doll because, inside the world created by the Vignette of Eternal Twilight, the Marquise has absolute power. However, Mithril knows that Dalian has a solution to beat the Marquise. The latter reappears, this time as a little girl. She summons gargoyles to kill Hugh and the others. Mithril won't be able to copy such creatures. She reflects the blows of the monsters with her silver knife. Hugh removes an avalanche of books from the Labyrinth Library to overload the Vignette of Eternal Twilight. Back to the real world, Marchbanks captures Mithril. She has no chance to oppose the strong man, who presses her against the floor.

Hugh and Dalian meet Shura outside the castle. The photojournalist wants a ride to the station. She's holding her breakfast instead of her broken camera. She's frustrated because, without her camera, she won't be able to write an article, and she will have to pay for all the travel expenses. Dalian refuses to give Shura a ride. The photojournalist tries to bribe the Biblioprincess with the breakfast.

Grosseteste shows up, satisfied because the Phantom Book Thief was finally caught. According to the inspector, Mithril is being guarded by reliable men. Marchbanks supposedly took the Faceless Book from her. However, Hugh reveals that Marchbanks is Mithril's henchman. The mask apprehended by the police is a fake. Marchbanks was the first to find the secret room with the Vignette of Eternal Twilight, but he decided to wait for his boss Mithril, who was disguised as Harban at the time. Grosseteste runs away to find the thief.

Shura feels sorry for the inspector. However, Hugh knows that the photojournalist is Mithril in disguise. After all, Shura would never part with her camera, even if broken. The thief smiles and removes her mask. She turns into a beautiful woman in white coat. Mithril usually prepares props in advance, but this time she failed to obtain a camera. The Faceless Book was unable to copy complex mechanisms. Dalian tries to hide her surprise. The Biblioprincess is furious because Mithril stole some books from her. The thief removes several thick volumes from her pocket. She had stolen them when Hugh opened the Labyrinth Library. She had used everyone in order to destroy the Vignette of Eternal Twilight and steal from Dalian. Mithril had sent a letter to the police because a policeman would be the perfect disguise. According to the thief, the real Harban is on vacation.

Mithril laments for the deaths of Dawson and Evelyn. Nonetheless, Hugh respects the thief. She saved Shura and freed Lyfia from the Marquise's curse. Perhaps that's why Hugh didn't hand Mithril over to Grosseteste. Mithril hands over the books stolen from Dalian. The thief would never have guessed that Dalian sealed cheap detective novels inside the Labyrinth Library. Hugh asks about the real Shura. Mithril had used her, preventing the photojournalist from writing about the Labyrinth Library. Dalian asks why Mithril collects Phantom Books. Mithril will answer the question only if the Labyrinth Library is opened. Although the thief is smiling, she seems sad and emotive. Mithril promises to steal from Dalian someday. Mithril puts on her mask. She jumps over a high wall, disappearing.

It's revealed that the real Shura was caught by the police. She yells, telling them that she's not a thief. The photojournalist promises to reveal Mithril's secrets as revenge for such humiliation. In the future, Shura became famous for writing an article with a bunch of information about the Phantom Book Thief.[2]


  • Mithril is a fictional metal found in the writings of J. R. R. Tolkien and in many other works of derivative fantasy. It is described as resembling silver but being stronger and lighter than steel. The author first wrote of it in The Lord of the Rings.[3]
  • The Phantom Thief is a special class of criminal in many types of art, just as likely to be an antihero as a villain. The thieves usually steal unique items using trickery and illusions and are masters of disguise, being recognized for their wit and audacity.[7]
  • Hal reflects that a female Asian doctor such as Yuna is not a common sight.[1] As for 2019, 4.4% of all staff of the United Kingdom's National Health Service are composed by asians.[8] Legislation was enacted allowing women to study medicine in 1875. As for 2018, almost 46% of all doctors on the United Kingdom's General Medical Council register were female.[9]
  • Shura knows Mithril as a police officer with the name resembling an alcoholic drink. She associates Harban with Bourbon. In turn, Hugh mistakenly calls him Harper and Pardon.[2]
    • Harban is a junsa.[2] In the Japanese law enforcement system, it's the lowest rank in a prefectural police officer's career.[10]
  • Griffin or griffon is a legendary creature, powerful and majestic. It has a eagle's head and wings, and the body, tail, and back legs of a lion. Since classical antiquity, griffins were known for guarding treasures and priceless possessions.[11]
    • In medieval heraldry, the griffin became a Christian symbol of divine power and a guardian of the divine.[11] Mithril uses a Phantom Book to gain divine powers.[1]


  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 The Mystic Archives of Dantalian light novel, Chapter 5, volume 4.
  2. 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 The Mystic Archives of Dantalian light novel, Chapter 3, volume 8.
  3. Mithril. (2020, April 14). In Wikipedia, The Free Encyclopedia. Retrieved 21:48, April 25, 2020, from https://en.wikipedia.org/w/index.php?title=Mithril&oldid=950871280
  4. Mithril Weapons. In The Ultimate Shining Force 2 Guide. Retrieved 22:19, April 25, 2020, https://sf2.shiningforcecentral.com/weapons/mithril-weapons/
  5. Mythril Knife. In Final Fantasy Wiki. Retrieved 22:19, April 25, 2020, from https://finalfantasy.fandom.com/wiki/Mythril_Knife
  6. Mithril knife. In RuneScape Wiki. Retrieved 22:19, April 25, 2020, from https://runescape.wiki/w/Mithril_knife
  7. Phantom Thief. In TVTropes. Retrieved 21:48, April 25, 2020, from https://tvtropes.org/pmwiki/pmwiki.php/Main/PhantomThief
  8. Carl Baker. (2019, July 8). NHS staff from overseas: statistics. In House of Commons Library. Retrieved 22:19, April 25, 2020, from https://commonslibrary.parliament.uk/research-briefings/cbp-7783/
  9. Dina Balabanova. (2018, June 20). NHS 70 series - How has the role of women in the NHS changed since its inception?. In London School of Hygiene & Tropical Medicine. Retrieved 22:19, April 25, 2020, from https://www.lshtm.ac.uk/newsevents/expert-opinion/nhs-70-series-how-has-role-women-nhs-changed-its-inception
  10. Prefectural police department. (2020, July 13). In Wikipedia, The Free Encyclopedia. Retrieved 23:38, August 29, 2020, from https://en.wikipedia.org/w/index.php?title=Prefectural_police_department&oldid=967405145
  11. 11.0 11.1 Griffin. (2020, April 1). In Wikipedia, The Free Encyclopedia. Retrieved 22:19, April 25, 2020, from https://en.wikipedia.org/w/index.php?title=Griffin&oldid=948568008


Dalian - Flamberge - Rasiel


Hugh Anthony Disward - Hal Kamhout - Professor

Recurring characters

The Girl in the Bookshelf - Wesley Disward - Kamilla Sauer Keynes - Jessica Elphinstone - Shura Irmania - Armand Jeremiah - The Perennial Wisdom's Owner - Oliver Grosseteste - Mithril - Hugh's mother - Hugh's father - Natalia - Hal's beloved - Miss Roedean

Creatures and machines

Atlantic Rim - Automaton - Beast of Ashwell - Book of Royal Power - Branches of Relationship - Broken Wings - Dantalian - Dead Book - Ghost train - Golem - Guignols - Guillemot - Heath - House-elf - Kasuruhau - Logbook - Loge's giant - Musical automaton - Pioneer Plant - The Harlequinade's creatures - Ras Alhague monster - Scarlet Robe - Sea devils - Steam Giant - The Queen of the Night - W Machine - Winged women - Wooden dolls - Zombies

Dalian Days

Priscilla Riley - Cecil Patreina - Margaret Manschwell


Male Characters - Female Characters
Phantom Book Users - Deceased Characters