Chapter Summaries

Mousse decided he needed to travel alone to Ohara before it was destroyed, but worried about gaining his family's permission and protecting himself. Princess Scarlett interrupted his plans and invited him to watch Dressrosa's arena tournament, leaving him interested in attending from the VIP seats.

• King Riku told Mousse that the West Blue held major centers of learning, reminding Mousse to visit Ohara before its books were destroyed.
• Mousse considered traveling alone to Ohara and worried about his family's approval and his ability to stay safe.
• Princess Scarlett slapped Mousse, and he warned her off by smashing the marble floor with his giant stone club.
• Scarlett explained that she had come to invite Mousse to a tournament celebrating the Betta fish's extermination.
• Mousse learned that the tournament offered two hundred million Berries in prizes and realized Scarlett's invitation might be his only way to watch from the VIP seats.

Mousse watched the Dressrosa arena tournament with Princess Scarlett and considered the kingdom’s poverty and the tournament’s rules. While using Observation Haki to assess the contestants, he discovered that his Book-Book Fruit had turned the information he sensed into precise data.

• Princess Scarlett begged Mousse to watch the arena matches, and her guard decided to report their growing closeness to King Riku afterward.
• Mousse observed Dressrosa’s poverty but chose not to intervene, fearing World Government suspicion and believing the Riku royal family was the root of the kingdom’s problems.
• A palace guard explained that the tournament required contestants to have a Doriki Value over 500 and excluded fighters who relied on dangerous special abilities.
• Mousse considered how concealing his own powers and learning about opponents would help him maintain an information advantage.
• Mousse used Observation Haki to estimate the contestants’ strength but struggled to judge those far stronger than himself.
• Mousse’s Observation Haki information began fluctuating and appeared as precise data, leading him to suspect his Book-Book Fruit had caused the change.

Mousse’s anomalous Observation Haki displayed everyone’s Haki reserves, leading him to conclude that Haki existed in all people before awakening and that innate vitality or mental power shaped its type and capacity. He left the arena understanding how to distinguish awakened Haki and still wondering why his own reserves were so vast.

• Mousse saw that ordinary spectators and contestants alike possessed Haki, confirming that Haki existed in people before they awakened it.
• Mousse reasoned that people with greater physical capacity tended to awaken Armament Haki, while those with stronger minds or sensitivity tended to awaken Observation Haki.
• Mousse realized that filling his Haki reserves and training might help him master Armament Haki, but his slow recovery made the process uncertain.
• Mousse noticed that his Haki reserves far exceeded those of everyone in the arena and considered whether his powerful soul explained his exceptional capacity.
• Mousse distinguished awakened Haki by its fluctuating reserves, while spectators’ fixed values indicated their Haki had not awakened.

Mousse realized that his datafied Observation Haki measured vitality rather than Combat Power and began considering how size distorted his estimates. He then spotted Charlotte Castard competing in Dressrosa and grew worried when her formidable opponent drew a katana and charged.

• Mousse watched a giant lose to a smaller swordsman and concluded that Observation Haki’s unusually high readings reflected vitality, not Combat Power.
• After observing more fights, Mousse reasoned that large bodies inflated vitality readings and that he needed enough battle data to develop a Size Correction Factor.
• Mousse recognized his sister Charlotte Castard in the tournament, and Princess Scarlett explained that Castard had come looking for him the previous day.
• Charlotte Castard faced a katana swordsman whose vitality reading exceeded three thousand, and Mousse worried that the closely matched fighters could seriously injure each other.

Mousse watched Charlotte Custard win an arena match and used the fights to reason through Haki expenditure, stamina, and Luffy’s victory over Katakuri. After Custard revealed she had come to Dressrosa and entered the arena, she joined Mousse in the front row.

• Charlotte Custard used her reach and Soru to defeat her opponent with a concealed Shigan after he launched a Flying Slash.
• Mousse applauded Custard and reflected on the advantages of height, reach, and agility.
• After watching several battles, Mousse concluded that fighters who used Haki at full strength could quickly exhaust it, making his large Haki reserves a major advantage.
• Mousse reasoned that Luffy had recovered his stamina and Haki by eating mochi during his fight with Katakuri, and that Katakuri could have won by stalling instead of fighting head-on.
• Mousse recognized Charlotte Custard when she covered his eyes, and she told him she had come to Dressrosa and entered the arena for its prize money.

Mousse learned from Charlotte Castard that his siblings’ allowances were limited and even Charlotte Amande was competing for the tournament’s prize money. He recognized Totto Land’s shortage of cash amid abundant supplies as resembling the Soviet Union’s economy and realized he might be able to improve the situation.

• Charlotte Castard took Mousse onto her lap and explained that her monthly allowance of 300,000 Berries barely covered cosmetics.
• Castard told Mousse that Charlotte Amande had entered the tournament for its 100 million Berries prize, despite being slated to become a minister and island lord.
• Mousse questioned why the family was short on cash despite Totto Land’s plentiful supplies and learned that most funds went toward strengthening the family.
• Mousse compared Totto Land’s economy to the Soviet Union’s, where abundant resources coexisted with shortages of money and goods the country could not produce.
• Mousse concluded that Totto Land’s limited cash income might not be difficult for him to increase.

Mousse considered how Totto Land might profit from export trade, then assessed the strength of the tournament contestants and Charlotte Amande. After discovering Amande’s impressive abilities, he wondered whether the Serpent Head Tribe faced a racial limit on swordsmanship.

• Mousse concluded that Totto Land’s export trade could be lucrative, but war with the Marines made it impractical, and he understood why Charlotte Amande wanted the tournament’s prize money.
• Mousse warned Charlotte Castard that the arena held formidable contestants, including the undefeated Kyros, but Castard remained confident in Amande’s chances.
• Mousse learned that Amande had skipped the preliminaries and estimated her strength at roughly five thousand Doriki, with Haki that ranked among the contestants’ best.
• Mousse connected Amande’s apparent progress plateau with the Serpent Head Tribe’s history of producing many swordsmen but no known Grand Swordmasters, leaving him questioning what limited them.

Mousse learned how swordsmanship ranks were distinguished and realized that Grand Swordmasters combined powerful Observation Haki with Armament Haki. He used his own ability to perceive weaknesses to damage marble with a fruit knife and a tray, naming the ability the Mind's Eye.

• Charlotte Custard told Mousse that swordsmanship ranks were generally based on reputation, but Charlotte Amande explained that swordmasters could cut steel and unleash Flying Slashes.
• Charlotte Amande said Grand Swordmasters could unleash casual, efficient Flying Slashes and perceive the weaknesses of all things, using Observation Haki to find weaknesses and Armament Haki to cut through them.
• Mousse wondered whether his strong Observation Haki could let him perceive weaknesses, and his perception suddenly made weak points in objects clear.
• Mousse used a fruit knife to scratch hard marble, prompting Charlotte Amande to suggest he might have a Sword Heart and Charlotte Custard to praise him.
• Mousse rejected the Sword Heart explanation, poked a hole through the fruit tray with his finger, and named his weakness-perceiving ability the Mind's Eye.

Mousse explored how Observation Haki could reveal weaknesses in people and weapons, while Charlotte Amande continued teaching him about swordsmanship. At the tournament, Charlotte Castard conceded her match against Amande, who then fought a fast and powerful Mink Tribe fighter.

• Mousse reasoned that Observation Haki could help him target weak points in human defenses and named his prospective technique Hokuto Shinken.
• Mousse learned that weapons could contain Armament Haki and wondered what made Black Blades special.
• Charlotte Castard won another match and advanced to the round of sixteen, where she conceded to her sister Charlotte Amande before their fight began.
• Charlotte Amande faced a gorilla Mink Tribe fighter whose supporters filled the stands, and she mocked him as a humanoid beast.
• The Mink charged at Charlotte Amande with tremendous speed, but she dodged and cut him deeply beneath the ribs.

Charlotte Amande used her unusual swordsmanship to slow the gorilla Mink and brutally torture him during the tournament. The gorilla Mink remained conscious and unable to surrender, while the horrified spectators began leaving the arena.

• The gorilla Mink recovered from Amande’s first attack, but she cut him again as his movements slowed.
• Mousse realized Amande’s swordsmanship altered the flow of time, slowing opponents while also affecting her own speed.
• Amande slowly drove her sword between the gorilla Mink’s ribs, leaving him unable to move or speak.
• The gorilla Mink broke down in tears, but the match continued because he could not surrender and had not lost consciousness or left the ring.
• Spectators fled the arena, and Princess Scarlett became frightened and disgusted by Amande.

Mousse watched Kyros interrupt Charlotte Amande’s execution in the arena, then investigated how soul strength might determine Haki and Devil Fruit abilities. Charlotte Linlin summoned Mousse to discuss Garp and Dragon’s sudden departure from Marineford, leaving him to assess whether it was genuine or a cover for an attack.

• Kyros knocked Amande’s sword away from the wounded Gorilla Mink, and the referee declared Amande the winner despite the interruption.
• Amande challenged Kyros after he insulted her, while Castard warned Mousse to stay away from her until the finals.
• Linlin summoned Mousse home, where he measured her and Katakuri’s vitality and Haki and concluded that Haki limits were likely tied to soul strength.
• Mousse wondered whether soul strength could also determine Devil Fruit power, but Linlin told him Garp and Dragon had returned to Marineford and left again the same day.
• Linlin asked Mousse to judge whether Garp and Dragon had truly departed or were preparing a surprise attack, and whether she should recall Oven and the others.

Mousse convinced Charlotte Linlin that Dragon had resigned and Garp had lost his drive after learning the truth about the Faros Incident. He then argued that Oven should return so they could test whether advanced Armament Haki made King's Fist easier to learn, and Oven arrived at Whole Cake Island to report on his training.

• Charlotte Linlin told Mousse that Dragon had resigned and that Garp had returned to sea after meeting with Dragon.
• Mousse concluded that the Faros Incident had driven Dragon to resign and Garp to lose his enthusiasm for Navy work, reassuring Charlotte Linlin about both men.
• Mousse urged Charlotte Linlin not to recall Oven, reasoning that Oven's slow progress with King's Fist might mean Elizabello II had withheld information.
• Mousse suggested that advanced Armament Haki might help someone learn King's Fist faster, so Charlotte Linlin ordered Brulee to bring Oven back.
• Brulee brought Oven from the Pudding Kingdom through the Mirror World, and he began telling Charlotte Linlin about his training.

Charlotte Oven struggled to master the King's Fist, but Charlotte Linlin quickly learned it and demonstrated its devastating power. Katakuri recognized the move’s long preparation time as a major weakness, while Mousse appeared poised to offer another surprise.

• Charlotte Oven said he could not yet retain Armament Haki long enough to complete the King's Fist’s charging stage.
• Katakuri praised Oven’s progress and became interested in how the technique could train Armament Haki.
• Charlotte Linlin accumulated Armament Haki without the warm-up motions, then punched at a cloud but failed to affect it.
• Katakuri suggested the King's Fist lost power over distance, so Charlotte Linlin tried again on a deserted island and made her Armament Haki rotate, destroying a distant cloud.
• Katakuri judged Charlotte Linlin’s punch powerful enough to threaten top fighters but noted that charging it took too long, then looked to Mousse for a possible solution.

Mousse discovered that the King's Fist could be charged rapidly by spending Haki, and Charlotte Linlin used the method to unleash a devastating Elbaf Spear. The attack nearly killed Mousse, but Katakuri shielded him, and the brothers were rescued from the sea.

• Mousse realized that the King's Fist could be charged much faster by converting Haki rapidly, and he tested the method with Charlotte Linlin.
• Charlotte Linlin mistook the technique for the true secret of the Elbaf Spear and instinctively struck Mousse with Ikoku Sovereignty.
• Katakuri grabbed Mousse and shielded him from the attack, and Big Head caught them before they fell into the sea.
• Katakuri reassured Mousse that he was alive, and Mousse complimented his uncovered face before Oven told Katakuri to stop hiding it.

Katakuri survived Charlotte Linlin’s powerful attack while shielding Mousse, and he and Mousse discussed how Armament Haki interacted with his hardened mochi. The family returned to the island, where they discovered that Charlotte Linlin had collapsed into a deep sleep after unleashing her attack.

• Oven confirmed that Katakuri was badly wounded but not in danger, and Katakuri explained that Linlin’s attack had not been fully charged.
• Mousse realized that Armament Haki did not cancel the Mochi Mochi Fruit’s properties, and Katakuri explained how hardened mochi had helped him withstand the blow.
• Mousse understood that Katakuri had risked his life to save him and felt grateful despite joking that his theory had helped Katakuri survive.
• Big Head carried Mousse, Katakuri, and Oven back to the island, where Perospero confirmed they were safe.
• Perospero told Katakuri that Linlin had fallen asleep after her attack, and Mousse suggested waking her while Perospero remained too frightened to approach.

Mousse concluded that Charlotte Linlin’s unconsciousness and amnesia were a defense against the trauma of believing she had killed her sons. After her memories returned, he suspected that repeatedly forgetting her terrible mistakes had kept her emotionally stuck as a child.

• Mousse told Perospero that Charlotte Linlin’s collapse and amnesia likely came from a psychological self-protection mechanism.
• Katakuri healed his injuries by eating vast quantities of mochi, using Life Return at the cost of speeding up his metabolism and shortening his lifespan.
• Katakuri built a hardened mochi wall to protect his siblings, then woke Charlotte Linlin, who did not recognize him or Mousse.
• After her children reminded her what had happened, Charlotte Linlin exclaimed and fainted again; when she woke, her memories had returned.
• Mousse reasoned that Charlotte Linlin could not mature because losing her memories kept her from facing and taking responsibility for her mistakes.

Charlotte Linlin tested Katakuri’s hardened mochi wall with increasingly powerful attacks, while Katakuri sought to measure the gap between them. The wall withstood even her Ikoku Sovereignty, and Mousse watched as Linlin prepared to attack again.

• Charlotte Linlin saw Katakuri’s mochi wall and angrily accused him of guarding against her.
• Katakuri provoked his mother and evaded her sword strike, which failed to crack the wall.
• Charlotte Linlin tried advanced Armament Haki and Conqueror’s Haki attacks, but the wall held.
• Katakuri told Perospero that he wanted to understand the distance between himself and Mother and believed there might be hope of dealing with her.
• Charlotte Linlin’s powerful Ikoku Sovereignty failed to pierce the wall, and Zeus caught her after the recoil blasted her away.
• Mousse praised Katakuri’s mochi and activated his Observation Haki as Charlotte Linlin prepared another Ikoku Sovereignty.

Mousse discovered that Charlotte Linlin and Katakuri had grown stronger as their confidence and conviction increased, while Charlotte Linlin began training with Katakuri. After watching them fight, Mousse examined Napoleon and found that the giant sword was unusually dull.

• Mousse scanned Charlotte Linlin and Katakuri and found that both of their Haki limits had increased, with Katakuri's rising more.
• Mousse reasoned that growing confidence strengthened conviction and Haki, creating a cycle that made the powerful grow even stronger.
• Charlotte Linlin praised Katakuri and invited him to train with her, surprising their family.
• Charlotte Linlin fought Katakuri with Napoleon, but his hardened mochi resisted her strikes and his evasive style let him avoid her attacks.
• Mousse inspected Napoleon and discovered that its blade was so dull that he questioned whether it was a sword or merely heavy exercise equipment.

Mousse persuaded Charlotte Linlin to fight without Napoleon, and her greater agility let her defeat Katakuri, though she accidentally injured him. She abandoned Napoleon and followed Mousse to his laboratory to make a new Homie, while Katakuri began recovering from his injuries.

• Mousse and Katakuri convinced Charlotte Linlin that her fists suited her fighting style better than Napoleon, so she dropped the sword and entered the fight unburdened.
• Charlotte Linlin struck Katakuri with a powerful punch, breaking three ribs and seriously injuring his internal organs, but he fused his bones and began healing.
• Mousse suggested that Charlotte Linlin create a new King's Spear, and she made Napoleon revert to an inanimate object.
• Mousse discovered that Napoleon's ordinary steel was not valuable enough to interest him, then had his eldest brother take him and Charlotte Linlin to his laboratory to make a new Homie.

Mousse helped Charlotte Linlin create a Liquid Oxygen Homie that could dramatically strengthen Prometheus, though the fusion injured the new Homie. He proposed strengthening it further to make their combined attack last longer and burn even hotter.

• Perospero realized Liquid Oxygen’s coldness could serve as the new Homie’s base property as Charlotte Linlin created it.
• Prometheus fused with the new Homie, turned white-hot, and melted a boulder into boiling lava.
• Mousse and Charlotte Linlin discovered that strengthening Prometheus with the new Homie injured it because its oxygen body was consumed in the process.
• Mousse proposed improving the new Homie’s base material so their fusion could last longer and grow more powerful.
• Perospero recognized that pure oxygen’s oxidizing power could make the fusion ignite steel and nearly any metal, while Charlotte Linlin agreed to strengthen the Homie.