Kenjaku

## Kenjaku

* Anime
* Manga

## Biographical Information

### Alias

Pseudo-Geto
Noritoshi Kamo (Formerly)
Kaori Itadori (Formerly)

## Professional Status

### Relatives

As Noritoshi Kamo* Cursed Womb: Death Painting (Sons)

As Kaori Itadori

* Jin Itadori (Former Partner)
* Yuji Itadori (Son)

### Affiliation

Pseudo-Geto's Group
Mahito's Group (Formerly)

## First Appearance

### Manga Debut

Chapter 10 (as Pseudo-Geto)
Chapter 145 (Named)

## Portrayal

### English Voice

Lex Lang (as Pseudo-Geto)

**Kenjaku** (羂 (けん) 索 (じゃく) , *Kenjaku*?) is one of the primary antagonists of the *Jujutsu Kaisen* series. He is an ancient curse user who has existed for over a thousand years using his innate technique, which allows him to transplant his brain into other people to control them. He has inhabited different individuals throughout the centuries and assumed their identities. Among those he has possessed include the blight of the Kamo clan who created the Cursed Womb: Death Paintings, Noritoshi Kamo, the mother of Yuji Itadori, Kaori Itadori, and Suguru Geto, who's corpse Kenjaku is currently possessing to exploit his Cursed Spirit Manipulation.

## Appearance

It is unknown what Kenjaku's original body looked like. He can only be distinguished by the stitches and scars that circle the top of his vessel's head. These are from the procedure required to transfer Kenjaku's brain, his only personal feature, into his host. Unlike a conventional brain, Kenjaku's has teeth.

In Suguru Geto's body, Kenjaku looks exactly as Suguru did during the Night Parade of a Hundred Demons, the day of his death.

Kenjaku in the manga (gray).
## Personality

Kenjaku is someone who has existed under countless identities for over a thousand years. There are even moments where he acts like whomever he's possessing unintentionally, such as when he caught himself suddenly acting like Suguru. Despite constantly assuming different identities, Kenjaku retains a strong core personality. He is calm and calculating, rarely displaying signs of panic or distress and often has entire scenarios planned out in advance. At times he can appear cheerful, playful, and even charming, but he is a manipulative, and deeply egotistical individual who will stop at nothing to further his ambitions regardless of who he harms.

While Kenjaku is uncaring and aloof when it comes to things that disinterest him, he's very talkative when it comes to himself or his interests. Kenjaku has a habit of going on long monologues and enjoys drawing out small talk with anyone, even his enemies. This can vary from casually educating someone on the state of the world or ruthlessly taunting his opponents. Kenjaku's demeanor is often optimistic and outspoken, but it carries an aura of condescension, which often infuriates those he is talking to, even his allies. Uraume in particular finds Kenjaku annoying and doesn't enjoy his company at all despite them being longtime comrades. Kenjaku is unapologetically arrogant because he possesses skills that back it up. This empowers him to carry his aura of superiority into dangerous situations. He will attack and severely injure someone all while casually explaining his ideals, goals, or abilities as if he's educating them. Even when faced with Satoru Gojo, Kenjaku made jokes and casually taunted him as if Satoru didn't confront him with the intent to kill.

Kenjaku doesn't intentionally intimidate anyone or control people through fear to get them to serve his interests. He manipulates them in clever ways using his charm to convince them they share a common goal. The mighty Sukuna, the calamity of aggression that disregards all else, worked with Kenjaku to split his soul into twenty cursed objects after death. Sukuna even protected Kenjaku from Satoru Gojo and agreed not to fight him before their agreement was concluded. While Kenjaku's manipulative tactics don't rely on fear-mongering, they don't rely on loyalty or respectful leadership either. Kenjaku simply knows how to play people and use their desires for his own ends. Kenjaku convinced hundreds of sorcerers over hundreds of years to join the Culling Game as a second chance at life, a situation they could thrive in as blood-thirsty warriors. Several curse users in Shibuya worked with Kenjaku in order to rid themselves of Satoru Gojo. In the case where an entity Kenjaku wants to use doesn't share an enemy or an objective, he will fabricate one. He went to a foreign power in the United States military and convinced them to invade Japan under the guise of abducting sorcerers to study cursed energy as a potentially sustainable resource. In reality, he tricked them into entering the Culling Game's colonies only to sacrifice their soldiers for his plan.

Kenjaku worked with Mahito's group of cursed spirits to work with him toward a world ruled by curses. While this isn't exactly what Kenjaku desires, his own interests aligned with theirs at the time. He gave them advice, spent time playing games with them, and supported Mahito and the others. However, Kenjaku believes himself superior to cursed spirits and was completely indifferent to the demise of Mahito's group in Shibuya. His only regret was not being able to absorb Jogo before his death. Kenjaku only stopped Yuji from exorcising Mahito so that he could absorb him and even thanked him for drawing out Mahito's strength.

Kenjaku's self-centered tendencies are driven by his boundless curiosity. Even after existing for hundreds of years, he's fascinated by the possibilities presented by cursed energy. He essentially wants to know the true potential of cursed energy in the form of a being and believes he can discover it by creating uncontrollable chaos. This is why he created the Death Womb Paintings only to discard them when he was disappointed with their "normal" outcome. He has no interest in anything unrelated to his ultimate goal and only looks to build toward his endgame. Never missing an opportunity to flaunt his ideals, Kenjaku discussed his goal with Yuki and Choso on two separate occasions. Kenjaku told Yuki Tsukumo that humanity's future lay in optimizing cursed energy and that, unlike Suguru Geto, he doesn't desire a world without cursed spirits. He admitted to Choso that he plans on merging the citizens of Japan into one entity simply because it seems like fun. He compared it to being a toddler holding a crayon with a blank piece of paper. Kenjaku even admitted that if that entity ended up being a funny face, that would be hilarious to him.

Tengen and Kenjaku used to be friends at some point but now Kenjaku considers the former a shut-in. He doesn't believe that's any way to exist and claims that he's truly lived by comparison. Having lived across a thousand years of conflicts and alliances, Kenjaku perceives the world as cursed one. He has profound contempt for all modern social structures, people, and philosophies that favor passivity and maintaining the status quo. He feels as if Japanese people incorrectly believe their lives are stable when in reality they're always on the brink of ruin. He knows not everyone will risk their lives while others are willing to die at any time without any hope for the future. Kenjaku despises both sides, believing that everyone should know the feeling of approaching their ideals step by step.

## Abilities and Powers

**Overall Skill Level**: Kenjaku is an ancient sorcerer who has accumulated a wealth of jujutsu-related knowledge and experience over the course of a thousand years. His advanced understanding of jujutsu sorcery is second to none with numerous feats that display his talent. As Noritoshi Kamo, Kenjaku invented the Cursed Womb: Death Paintings and became known as the evilest curse user in history. He is the only person who knows how to turn a sorcerer into a cursed object after death, something not even Sukuna knew how to do during the Heian Era. He is also the second most powerful barrier user after Tengen, recognized as one of few sorcerers who can match them in barrier techniques.

Kenjaku possesses the bodies of other sorcerers and utilizes their techniques in addition to his own natural skillset. He uses Cursed Spirit Manipulation with the same degree of skill as his current host, Suguru Geto. He took Suguru’s body specifically for this technique and has a masterful understanding of how it works and how best to use it for his ambitions. He forced Mei Mei, a grade 1 sorcerer who is familiar with Geto's technique, to retreat.

Kenjaku not only expertly applies the technique to battle but used its applications to set up his schemes as well. For example, he absorbed Mahito with Cursed Spirit Manipulation and then used Mahito’s Idle Transfiguration to set up the Culling Game. He also used the technique to absorb Tengen, who had evolved into a more cursed spirit than human, continuing to further his own ends.

Kenjaku’s talent extends well beyond jujutsu sorcery. He is an excellent unarmed combatant, is highly intelligent, and is an unrivaled mastermind when it comes to underhanded schemes. Kenjaku was the orchestrator of both the Shibuya Incident and the Culling Game, two of the largest jujutsu terrorist events in modern history. Not only were they both effectively set up and executed, but went nearly perfectly to plan. The Shibuya Incident successfully sealed Satoru Gojo, the strongest sorcerer of the modern age. Kenjaku and Uraume effortlessly held off a group of sorcerers who attempted to reclaim Satoru at the end of the incident. Yuji Itadori was completely outclassed against Kenjaku and even Choso was unable to deal any significant damage. Not only did Kenjaku escape unscathed with Prison Realm, but successfully began preparations for the Culling Game as well.

The combination of Kenjaku's ambition, manipulative tactics, and overall talent in jujutsu allowed him to establish a convoluted competition like the Culling Game. He used a complex blend of several sorcery techniques to create the Culling Game. So complex in fact, that Tengen had to hold an in-depth conversation with their allies to explain exactly how the Culling Game operates. Kenjaku invited a thousand players over the course of millennia, set up numerous colonies using Tengen’s pure barriers as a foundation, and established the rules of the game using a series of intricate binding vows. Some of the vows Kenjaku took upon himself include not being a game master and to end what was permanent. Kenjaku's plan was so well thought out that his enemies, the Jujutsu High sorcerers, had no choice but to participate.

Kenjaku displayed the full range of his abilities when he bested Yuki Tsukumo, a special grade sorcerer, Choso, a special grade Death Painting Womb, and Tengen, all by himself. His barrier prowess enabled him to invade the Tombs of the Star without trouble, something Tengen had no doubts he’d be able to accomplish. One-on-one, Kenjaku had Choso completely overmatched and his opponent was unable to land a single hit. Initially, Kenjaku easily overpowered Choso using only low-level cursed spirits reinforced with his cursed energy. Even when Choso managed to surprise his creator, he failed to land an attack because Kenjaku possessed another cursed technique. Kenjaku wanted to win without revealing this technique but his arsenal of sorcery abilities are what ultimately pushed him to victory.

Yuki proved a far greater challenge than Choso, capable of overcoming any cursed spirit Kenjaku threw at her. He was forced to use everything in his arsenal to defeat Yuki, displaying his most advanced feats of jujutsu to date. As a master of barriers, Kenjaku possesses the divine skill to expand his domain without enclosing the outer shell. Only he and Sukuna are capable of doing so, not even Satoru Gojo can expand his domain without closing the barrier. The strength of Kenjaku’s barrier ripped Yuki’s simple domain to shreds and his domain’s can’t-miss attack dealt massive damage.

Even with his domain dispelled and his cursed techniques burnt out, Kenjaku held his own against Yuki and Choso at the same time. When backed into a corner, he used clever, unpredictable, spur-of-the-moment actions to survive. (i.e. removing the top half of his head off to deflect Choso’s Piercing Blood). Unlikely to brute force his way past Yuki, Kenjaku won by outsmarting her. He let her believe victory was at hand so she’d be caught off guard by the clever ways he used his techniques. Kenjaku even survived Yuki’s last-ditch effort, a black hole, by yet again using a complex blend of jujutsu mechanics.

Kenjaku’s victory over Yuki and Choso made their allies, other powerful sorcerers, recognize that he could not be defeated with conventional means. While Kenjaku openly recognizes that he is no match for Satoru Gojo, he confidently takes on any other opponent in his path. With Suguru Geto's body, he wields an army of cursed spirits capable of single-handedly conquering a nation.

**Master Hand-to-Hand Combatant**: Kenjaku possesses masterful skills in close combat that can stand up to nearly any opponent. Like Suguru Geto, Kenjaku is a highly capable close-range combatant despite being a curse manipulator. He mainly uses taijutsu to supplement his sorcery, but Kenjaku is fully capable of relying on hand-to-hand combat if need be.

Kenjaku effortlessly caught Kasumi Miwa's katana while unarmed and snapped the blade with a simple clench of his fist. Moments later he held off Choso's assault in Shibuya with contemptible ease. Kenjaku casually parried every strike Choso threw at him while easily landing his own hits.

In the Tombs of the Star, Kenjaku once again made taking out Choso look easy by using close combat in combination with Cursed Spirit Manipulation. Yuki Tsukumo, who specializes in close combat, proved more of a challenge. However, Kenjaku held off both Yuki and Choso at the same time on his own. Kenjaku's cursed techniques were burnt out and he was forced to rely solely on taijutsu to survive. While he couldn't get off any attacks due to the sheer volume of offense coming at him, Kenjaku effectively defended himself until his techniques were replenished while only suffering moderate damage.

**Immense Tactical Intellect**: As previously stated, Kenjaku is a thousand-year-old individual with a vast amount of knowledge acquired over hundreds of years of existence. This includes general expertise, a comprehensive understanding of sorcery, and strategic intellect. He is extraordinarily clever and a masterfully calculating criminal mastermind. This is due to his wealth of knowledge on jujutsu sorcery and his talent for manipulation and tactical forecasting.

Kenjaku's intellect, along with his focus and patience are what makes him most cunning. He was willing to wait hundreds of years to create the proper conditions to accomplish his goals. His careful consideration and planning are what allowed Kenjaku's schemes to overcome the Six Eyes after losing to it multiple times in the past. Kenjaku analyzed Satoru Gojo to come up with a proper strategy to get the nigh-unbeatable sorcerer out of his way. He saw that Satoru was strongest fighting alone and as a countermeasure, Kenjaku orchestrated the Shibuya Incident to put him in unfavorable conditions. While Satoru was stifled by non-sorcerers and forced to combat several special grade cursed spirits at the same time, Kenjaku waited for just the right moment to seal him. Kenjaku also had the foresight to make sure nobody from Jujutsu High saw him as Suguru Geto, as this would've ruined the surprise that was key to distracting and sealing Satoru Gojo.

With his primary obstacle removed, Kenjaku immediately moved on to his next well-thought-out and extremely convoluted scheme. The Culling Game was created as a means for Kenjaku to achieve his primary goal of merging the Japanese population with Tengen. He launched the Culling Game directly after the Shibuya Incident, having fully prepared for it beforehand. Over the course of numerous generations, Kenjaku recruited sorcerers from different time periods to participate. He is the only sorcerer who knows how to transform someone into a cursed object after death, a major testament to his unmatched knowledge of jujutsu sorcery. Kenjaku even accounted for the return of Satoru Gojo and avoided a surely fatal encounter with him by forging an alliance with Sukuna.

Kenjaku's aforementioned mastery of sorcery is appropriately applied to battle. He is a cerebral fighter who can accurately analyze his opponent's abilities and use his own to overcome them in clever and complex ways. Yuki Tsukumo is one of the few sorcerers that Kenjaku encountered whom he didn't have any prior information. He was well aware of Choso's weaknesses and took advantage of them to easily overpower the Death Painting Womb, but this didn't apply to Yuki. Kenjaku analyzed Yuki throughout their battle and had to take numerous risks in order to overcome her. He began their battle by trying to keep her at a distance to observe her skills, a solid strategy that ended up backfiring. Even though he lost the exchange, Kenjaku recognized that his opponent still found his abilities troublesome. Immediately after seeing Yuki's hesitation to open a domain, Kenjaku expanded his own domain and ended up dealing massive damage.

Kenjaku displayed a talent for thinking on his feet when Choso joined Yuki's side and ambushed him. Although Choso's ambush surprised Kenjaku, he quickly adapted and avoided a fatal blow. Kenjaku ultimately defeated Yuki with deception, a sorcerer's greatest weapon. He had her believe that he was using cursed spirit manipulation to buy time for a gravity attack. This lured Yuki into range, where Kenjaku surprised her with a miniature maximum Uzumaki and dealt the finishing blow.

### Jujutsu

Kenjaku's innate technique allows him to swap bodies with another person, even if they are dead, by transplanting his brain into the body of his target. After the transplant, this technique leaves a stitched scar running horizontally through the forehead. Kenjaku can remove the top part of their head to reveal his original brain.
Once inside a body, Kenjaku gains access to the host's cursed energy, all their innate techniques, and memories. Even the Six Eyes cannot recognize him as an imposter as he retains the host's cursed energy. Kenjaku can live more than a thousand years thanks to his cursed technique while inhabiting different bodies.
As shown with his usage of Kaori Itadori’s technique fighting Choso and Yuki, its been hinted that even when switching to a new body, Kenjaku retains access and usage of his former host’s innate cursed techniques. Even if Kenjaku could collect different cursed techniques from his previous hosts there's a limit to how much his brain can store before overloading.

**Suguru Geto** (夏 (げ) 油 (とう) 傑 (すぐる) , *Getō Suguru*?): After Suguru Geto's defeat at the hands of Yuta Okkotsu, Kenjaku transplanted his brain with his innate technique into Suguru's body and has taken Geto as his host body, effectively giving Kenjaku access to all of Geto's memories, skills, and jujutsu. This is where he could now apparently access all of Geto's techniques.

**Cursed Spirit Manipulation** (呪 (じゅ) 霊 (れい) 操 (そう) 術 (じゅつ) , *Jurei Sōjutsu*?): A technique where the user can summon and control naturally formed cursed spirits for a desired purpose. Due to gaining Geto's body, Kenjaku can utilize this technique as if it is his own innate technique. Thanks to this technique, Kenjaku was shown to have acquired numerous cursed spirits as his personal familiars. He has deployed them to fight off multiple opponents and bombard them with a variety of different cursed techniques that each curse possesses. One of the cursed spirits he acquired was the Smallpox Deity, which was a powerful special grade cursed spirit capable of casting its own Domain Expansion. As shown during its battle against Mei Mei, it was powerful enough to nearly corner her if not for her brother's assistance to distract it and give her a chance to finish it off. Later, he absorbs Mahito after he is weakened by Yuji Itadori.

**Maximum: Uzumaki** (極 (ごく) ノ (の) 番 (ばん) 「うずまき」, *Gokunoban・Uzumaki*?): The maximum technique of Curse Spirit Manipulation combines a massive number of collected curses into one powerful attack. Uzumaki extracts a curse's innate technique when used with cursed spirits of semi-grade 1 or higher, allowing the user to keep the techniques for one-time uses. Kenjaku first used this technique against Kasumi Miwa using Mahito, allowing him to extract Idle Transfiguration.

### Former Jujutsu

**Idle Transfiguration** (無 (む) 為 (い) 転 (てん) 変 (ぺん) , *Mui Tenpen*?): After expelling Mahito via the Maximum: Uzumaki technique, Kenjaku gained his innate technique for a one-time use. Idle Transfiguration granted Kenjaku the ability to reshape other people's souls and potentially himself. He used it on Tengen's barrier to kickstart the Culling Game by remotely altering the souls of the people he marked over the years.

## Equipment

**Prison Realm** (獄 (ごく) 門 (もん) 疆 (きょう) , *Gokumonkyō*?) is a special grade cursed object containing a barrier capable of sealing absolutely anything or anyone inside of an inescapable pocket dimension. It was the crux of his plan to seal Satoru Gojo in Shibuya. The plan took place on October 31st, and sealing was completed according to Kenjaku's plan. Kenjaku is the bearer of the "front gate" of the Prison Realm. As the bearer, only he has the authority to open the "back gate" of the Prison Realm, which was in the hands of Tengen. However, it is possible to unseal the target from the realm by breaking it open with a cursed technique that can cancel or nullify other cursed techniques.

## Battles & Events

**Shibuya Incident Arc**

* The Shibuya Incident
	+ Mei Mei vs. Kenjaku (Offscreen)
	+ Jujutsu Sorcerers vs. Kenjaku & Uraume

**Culling Game Arc**

* Culling Game (Orchestrator)
* Yuki Tsukumo & Choso vs. Kenjaku

**Shinjuku Showdown Arc**

* Kenjaku vs. Iori Hazenoki
* Fumihiko Takaba vs. Kenjaku

## Trivia

* According to Jujutsu Kaisen Official Fanbook:
	+ He was able to take over Geto because his body was not cremated.
	+ He doesn't heal the scar on his forehead because it's a Binding Vow.
	+ The brain that takes over Geto's body is a physical part of Kenjaku's flesh so that ordinary people can see him. He has his own technique in the body that he left behind so that he can have two cursed techniques. When he moves over, the technique from his original body disappears, but he has a lot of tricks up his sleeve.
	+ Mahito's group does not know someone has taken over Geto's body. They think he is a curse user who knows a lot.
	+ He has a strictly business-only relationship with the other cursed spirits. In reality, he looks down on the cursed spirits who have organized themselves to overtake humanity and doesn't take them too seriously.
	+ He can use his technique on his fellow cursed spirits in a one-on-one fight. Nonetheless, he believes Jogo and Mahito will be particularly tough.
	+ He has never considered taking over the bodies of Gojo and Toji. Gojo is an impossible option since he is unbeatable. Toji isn't impossible, but if Kenjaku was to take over Toji's body, there’s a chance that Toji's Heavenly Restriction and Kenjaku's technique may clash.

## References

*Jujutsu Kaisen* Manga: Chapter 136 (p. 16).
2. ↑ *Jujutsu Kaisen* Manga: Chapter 90 (p. 15-17).
3. ↑ 3.0 3.1 *Jujutsu Kaisen* Manga: Chapter 134 (p. 16-18).
*Jujutsu Kaisen* Manga: Chapter 134 (p. 1).
*Jujutsu Kaisen* Manga: Chapter 215 (p. 1).
*Jujutsu Kaisen* Manga: Chapter 216 (pp. 3, 11).
*Jujutsu Kaisen* Manga: Chapter 222 (p. 12).
*Jujutsu Kaisen* Manga: Chapter 221 (p. 11-12).
*Jujutsu Kaisen* Manga: Chapter 221 (pp. 13, 17).
*Jujutsu Kaisen* Manga: Chapter 228 (p. 14).
*Jujutsu Kaisen* Manga: Chapter 176 (p. 8).
*Jujutsu Kaisen* Manga: Chapter 161 (p. 3).
*Jujutsu Kaisen* Manga: Chapter 187 (p. 19).
*Jujutsu Kaisen* Manga: Chapter 96 (p. 12).
*Jujutsu Kaisen* Manga: Chapter 209 (p. 11-16).
*Jujutsu Kaisen* Manga: Chapter 133 (pp. 10, 18).
*Jujutsu Kaisen* Manga: Chapter 136 (p. 9).
*Jujutsu Kaisen* Manga: Chapter 136 (p. 5-6).
*Jujutsu Kaisen* Manga: Chapter 202 (p. 17-19).
*Jujutsu Kaisen* Manga: Chapter 209 (p. 9).
*Jujutsu Kaisen* Manga: Chapter 222 (p. 4-5).
*Jujutsu Kaisen* Manga: Chapter 145 (p. 9).
*Jujutsu Kaisen* Manga: Chapter 134 (p. 18).
*Jujutsu Kaisen* Manga: Chapter 228 (p. 14).
*Jujutsu Kaisen* Manga: Chapter 145 (p. 8).
*Jujutsu Kaisen* Manga: Chapter 206 (p. 5).
*Jujutsu Kaisen* Manga: Chapter 133 (p. 14).
*Jujutsu Kaisen* Manga: Chapter 134 (p. 2).
*Jujutsu Kaisen* Manga: Chapter 102 (p. 19).
*Jujutsu Kaisen* Manga: Chapter 137 (p. 7).
*Jujutsu Kaisen* Manga: Chapter 136 (p. 6-7).
*Jujutsu Kaisen* Manga: Chapter 145 (p. 7-8).
*Jujutsu Kaisen* Manga: Chapter 208 (p. 19).
*Jujutsu Kaisen* Manga: Chapter 133 (p. 12-16).
*Jujutsu Kaisen* Manga: Chapter 135 (p. 4-17).
*Jujutsu Kaisen* Manga: Chapter 136 (pp. 11—13, 16).
*Jujutsu Kaisen* Manga: Chapter 145 (p. 11-13).
*Jujutsu Kaisen* Manga: Chapter 216 (p. 3).
*Jujutsu Kaisen* Manga: Chapter 202 (p. 8-9).
*Jujutsu Kaisen* Manga: Chapter 203 (p. 16).
*Jujutsu Kaisen* Manga: Chapter 204 (p. 17-18).
*Jujutsu Kaisen* Manga: Chapter 206 (pp. 6, 9-10).
*Jujutsu Kaisen* Manga: Chapter 207 (pp. 5—12, 17-19).
*Jujutsu Kaisen* Manga: Chapter 208 (p. 1).
*Jujutsu Kaisen* Manga: Chapter 208 (p. 13-18).
*Jujutsu Kaisen* Manga: Chapter 222 (p. 12-13).
*Jujutsu Kaisen* Manga: Chapter 203 (p. 15).
*Jujutsu Kaisen* Manga: Chapter 135 (p. 9).
*Jujutsu Kaisen* Manga: Chapter 135 (p. 6-7).
*Jujutsu Kaisen* Manga: Chapter 207 (p. 7-9).
*Jujutsu Kaisen* Manga and Anime: Chapter 134 (p. 1-2) and Episode 46.
*Jujutsu Kaisen* Manga: Chapter 205 (p. 14).
*Jujutsu Kaisen* Manga: Chapter 208 (p. 18).
*Jujutsu Kaisen* Official Fanbook: .