Light Novel Volume 18/Synopsis

Prologue: The Meeting to Discuss Efficient Eating Enhancement
The day after the petrified Kizuna was rescued, Naofumi prepared an extremely large breakfast for the heroes. Still full from last night's meal, Glass and L'Arc lead the protest against Naofumi's force-feeding. However, Naofumi - still excited about his new eating enhancement power-up method - doesn't understand their hesitation. Glass proposes that they focus on creating a small amount of very high-quality food instead of an extreme amount of good food. While Glass, L'Arc and Raphtalia discuss options to get the ingredients, Naofumi feeds Filo, Sadeena, Shildina and S'yne. As the big eaters talk with Naofumi, the discussion moves towards body-types and relationships. While Naofumi is warming up to the idea of relationships, he still isn't personally ready for one. Since there are ingredients that make a person lose weight or increase their metabolism, obesity would not be a problem. Coming back to L'Arc, Glass and Raphtalia, Naofumi agrees to compromise and provide food efficiently without overfeeding. He also considers finding more advanced recipes.

Chapter One: Sloth
After breakfast, Naofumi, Glass and Raphtalia head to where Kizuna's petrification treatment was finally being completed. As the paralysis was lifted, a cursed aura surrounded Kizuna and she became extremely lethargic and reluctant to do anything except sleep. When Glass tried to rouse Kizuna, a cursed smoke of slothfullness billowed out of her which resisted any interference. Naofumi realized that the vanguards of the waves must have forced upon Kizuna a cursed weapon of sloth. With her torpor and a interfering accessory, Kizuna was unable to switch out of the cursed weapon which was giving her constant slothfullness. Ethnobalt suggests going to his home, the Ancient Labyrinth Library, to look for a way to lift this curse. Naofumi agrees and assembles most of his companions to accompany him.

Chapter Two: Library Search
Naofumi uses his Vassal mirror to teleport his party to the Ancient Labyrinth Library. Ethnobalt catches up with the other library rabbits and the rest of the party meet up with Altorese. They were able to confirm with Alto that descriptions of Malty, Mald and S'yne's sister have been spreading for their capture. Ethnobalt rejoins them and uses his library rabbit abilities combined with the Vassal Book to determine the general location of the book with the answers they need. Fighting through the labyrinth, they come to a large door with the symbol for the four Legendary Heroes. Naofumi uses his status as a Holy and Vassal weapon holder to unlock the door and they continue on. Eventually, they are led to a bookcase with a secret switch and a second door with symbols that look like Q'ten Lo's sakura lumina trees. Raphtalia uses her ability as the 'pacifier' and Heavenly Emperor of Q'ten Lo to open the door with Glass' help. They then come to the chamber of the master librarian. Inside they find a glowing vial with murals of the holy and vassal weapons. Ethnobalt uses his authority to release the vial and finds the book with the information needed to break the curse. The group decides to head back and S'yne teleports them back to the dungeon entrance

Chapter Three: Fishing Fool's Determination
Returning to Kizuna, Glass uses the vial to remove the illegitimate accessory from Kizuna's Legendary Hunting Tool. However, her curse continued to grow and she remained unwilling to change her weapon. Attempting to motivate Kizuna, they drag her on a ship and cast her rod for her. S'yne and Naofumi taunted her while Sadeena and Shildina pretended to be fish. With their efforts combined, they were able to inflame Kizuna's passion for fishing and break the curse as she finally changed from the sloth rod.

Chapter Four: Sisters and Jealousy
With Kizuna's recovery, the group returned to L'Arc's castle and they catch her up on the latest events. They also meet Yomogi and Tsugumi who have been acting as ambassadors for Kizuna and the heroes. Together, they decide to celebrate Kizuna's return. Naofumi also decides to cook a feast for the celebration.

Before the celebration starts, Naofumi and Kizuna drop off Ethnobalt at the Ancient Labyrinth Library. Apparently, the vial of poison that saved Kizuna is also a lost potion that officially turns a library rabbit into the master librarian of the labyrinth library. With the library rabbits' approval, Ethnobalt drinks it and officially take his roll as master librarian. Back at the celebration, Kizuna, Tsugumi and Yomogi experience Naofumi's addictively good food. While stuffing their mouths, Tsugumi mentions a place renowned for their good food. Looking to increase the quality of food, everyone decides that they should travel to this town and meet the chef.

Chapter Five: Ultimate Soup Stock
Overnight, Naofumi practised cooking and experiments to try to optimize his magical cooking skills. He also spent his time creating different stocks for future recipes. After telling the other heroes that they must also learn to cook good food in order to make use of the food level power-up method, they prepare to go to the famous cooking town the next morning.

Chapter Six: Seya's Restaurant
The day after making the stocks, Naofumi and a large group of his companions head to the town housing the famous chef. Itsuki, Rishia and Ethnobalt stayed behind to study ancient texts. Entering the town, they noticed that it had a curious, almost dangerous atmosphere. However, Naofumi and his party were immediately welcomed. Heading towards the restaurant, they noticed that the residents were singularly obssessed with "Master Seya's" cooking.

Entering the restaurant, they are told that the meals are free and that as they contribute more to Master Seya, the better food they can get. They order the food and as soon as Naofumi is about to take a bite, his Legendary Shield warns him of some toxins. He ignores it and alters his toxin sensing ability. When the hostess comes to check in on everyone, it seems that everyone is disappointed in the food and compares it to Naofumi's. Immediately, the hostess and all of the surrounding patrons are insults and prepare to attack them. Just as a fight was about to start, Seya comes out to check on the commotion. After hearing about Naofumi's superior food, he puts down a cooking challenge. Naofumi immediately refuses but it reluctantly convinced by the rest of his party to participate.

Chapter Seven: Contentious Cooking Battle
As Naofumi enters the kitchen for the cooking battle, it became immediately clear that it would not be a fair fight. Naofumi was given terrible quality food and the judges have been bribed. The MC, Trash III, was also clearly on Seya's side. However, Naofumi would be able to collect his own ingredients and he was also given some decent ones due to the opponent's incompetence. Looking over at Seya's side, Naofumi realised that the opponent was touting store-bought premade curry as the best food in his repertoire. He just added an addictive ingredient and then boiled the curry bag. Using his instant food, Seya finished quickly. Naofumi heads out to collect ingredients from L'Arc's castle. On the way, he meets a boy who gives him ingredients and mentions that Seya's cooking has killed some of his family. Naofumi quickly returnedg to the cooking battle with more ingredients. Together, Naofumi and his team were able to create multiple dishes for the judges before time ran out.

Chapter Eight: Medicinal Cooking
Before the food was passed to the judges, Trash III and the judges clearly expressed that Seya was going to win. However, once the judge tried Naofumi's first dish, they were instantly surprised by the deliciousness. The judges continued to wolf down all of Naofumi's dishes as he explained the food and the medicinal herbs he added in. After they finished, it was time for Seya's cooking. As soon as Seya's soup touched their tongue however, they spat it out. Even Trash III tried it and thought it was disgusting. After being called a cheater, Naofumi reveals what has been going on.

Apparently, Seya has been adding addictive substances into his food. To combat this, Naofumi added a large amount of medicinal herbs to expel the toxins and add vitality. Now that the judges were no longer addicted to the food, the incredible taste of the addictive substance was no longer appealing. Seya immediately resumes calling Naofumi a cheater. In the end, the judged proclaimed Naofumi as the winner.

Chapter Nine: Resolution via Violence
At the judges proclamation, Seya and the crowd erupt in anger. At Seya's word, the seated diners used whatever they had on hand to attack Naofumi and his party. Using his addictive doping powder, he buffed his waiting staff to attack the heroes. Looking closely at Seya's soul, Sadeena and Shildina suspect him to be another vanguard of the waves. As they take the head of the attacking mob, Kizuna switches to her new weapon acquired from the vial and learns that she can remove the effects of the doping, or 'illegitimate power', out of the crowd. Seya attempted to steal Raphtalia's Vassal Katana but Kizuna's new weapon was also able to prevent it. Finally, Therese and Shildina were able to use suppression magic to lull the crowd to sleep. As Seya lost, his harem of waitress staff immediately rejected him. At Seya's defeat, Naofumi offered him a deal: write down who his superior is and then Naofumi will let him go. Seya immediately accepts but as he does his head blows up.

During the next few days, Naofumi helps out the town detox from the addictive substance that Seya was using. A week later, the town was back to normal and Naofumi had taught the chefs how to feed to town. Back at L'Arc's castle, Naofumi prepares a meal for the heroes. However, this time he makes a special effort not to overfeed them which they all greatly appreciate.

Chapter Ten: Dragon of Ultimate Magic
After the issues with Seya's town had been resolved, the heroes come together for a strategy meeting. They plan to release at least one of the three captured Holy Weapons of Glass' World so that the heroes from Raphtalia's world may be able to use their weapons and magic again. They task Ethnobalt to search into methods to combat S'yne's sister and the vanguards of the waves. Finally, Therese suggests reviving the Demon Dragon, one of the Guardian Beasts of Glass' World, to learn what it knows about buff-nullifying magic. Kizuna and the other heroes are immediately disgusted by the idea but with the overwhelming power of their enemies, they decide that there is no choice.

A little while later, the group conduced the ritual required to revive the Demon Dragon as a baby dragon enslaved under Kizuna. After negotiations nearly broke down, the demon dragon agrees to perform the level limit break ceremony on the hero's party as long as she regains her regains her emperor fragments. Along the way, all of the heroes' demon dragon weapons got an upgrade. The Demon Dragon hints that the technique to cancel out dispelling magic may come from Glass' ancestors

Chapter Eleven: Volunteer Soldiers
With the Demon Dragon's information, Naofumi and his group head to where Glass' style origination. However, as they were making their way, a large number of volunteer soldiers started gathering at L'Arc's castle due to information leaks. Naofumi recruits Sadeena and Shildina to search for any souls of the vanguards of the waves within the volunteers. After a while, Naofumi checks back in and the two killer whale sisters point out all of the enemies that they could find. As they went to gather up the enemies, S'yne's sister appeared with Elena and another vanguard of the waves at her side. After some initial argument, the two sides started to fight.

The vanguard, or "Enemy of the Week" had the ability to create transparent walls and started crushing the surrounding volunteers. The heroes saved the volunteers but were unable to pierce the enemy's defence. At the same time, S'yne's sister activated an Artificial Behemoth which started to rip into the heroes.

Chapter Twelve: Double Reflection
As the Artificial Behemoth starts tearing into the heroes, the Demon Dragon points out that it is made of a corrupted Holy Weapon. However, Kizuna was able to hold off the behemoth by herself since her Legendary Weapon specializes in monsters. At the same time, Naofumi's companions and the Demon Dragon cast a power attack spell and targeted it towards Naofumi. Naofumi used his Vassal Mirror to amplify the spell and reflect it towards the enemies. S'yne's sister teleported away but Elena and the enemy of the week get incinerated and their souls got eaten by the Demon Dragon. Finally, since the party could focus on the Artificial Behemoth together, they were able to defeat it. Unfortunately, S'yne's sister came back and stole the Holy Weapon before the heroes could restore it.

Chapter Thirteen: The Reborn
The heroes regathered after the battle with S'yne's sister and the vanguards of the waves. Naofumi commissions S'yne to create something to prevent the enemy from running away and the killer whale sisters prepare to look for a spy in L'Arc's forces. Itsuki also excitedly mentions that Kizuna and Ethnobalt were finally able to make a translation of the ancient text from the Ancient Labyrinth Library. The text mentions that there is some 'god' which is causing the different worlds to 'hit' each other which is causing the waves. Apparently, the Holy Weapons and Vassal Weapons cannot defeat the enemy by themselves and require outside help to defeat this 'World Eater.' After musing about this self-proclaimed god and the multitude of vanguards of the waves, Naofumi asks Raphtalia to draw the soul out of one of the vanguards that they had captured. Sure enough, the soul was of an 30 year old Japanese man. Naofumi realized that the vanguards of the waves are similar to Legendary Heroes - people reincarnated from Japan and given special abilities. This has been happening for many years and is responsible for the loss of records of the Guardian Beasts and the decline of Hengen Muso. It also means that the purpose of Q'ten Lo's barrier is to prevent these souls from entering Q'ten Lo.

Epilogue: The Game Knowledge Pitfall
Later that night, the heroes eat and discuss the significant of the earlier discovery. Itsuki suggests that the self-proclaimed 'god' is the one who gave Itsuki and the other heroes misleading information through the games they played in the Japanese lives. This game knowledge and the preconceived notion that this world was a game had led to the deaths of all of the other Holy heroes besides Kizuna in Glass' World and nearly killed Ren, Itsuki, and Motoyasu. They also discuss the potential uses for Kizuna's new tool which rejects illegitimate power. The heroes then rest and prepare for their journey ahead.