Light Novel Volume 19/Synopsis

Prologue: An Exchange of Otherworldly Information
This volume starts with the aftermath of a wave within Glass' World. The Heroes easily repel the waves and find that this wave connects to Raphtalia's World. Taking this opportunity, Rishia and Raphtalia enter the dimensional rift to update the heroes on the other side. After a few minutes, Raphtalia comes back with Eclair who updates Naofumi and his group about current events in their world. After the debriefing, the old Hengen Muso lady arrives in Glass' World. After their updates are complete, Rishia comes back to Glass' World while Ruft and Eclair return to their world.

Chapter One: A Visit to the Head Temple
Over the next few days, the heroes continue to level up and train until they finally decided to go to Glass' original country to find a way to stop nullification magic. Glass and Kizuna explain that while Glass was selected as the Vassal Fan wielder, many of her fellow students felt jealous and caused all sorts of problems. As soon as they arrive within the temple in Glass' country, Naofumi, Glass and their companions are attacked. However, the attackers are easily repelled. Once the attackers are defeated, Glass' Master's welcomes them to his dojo. Glass asks him about ways to repel nullification magic but her master admits that those techniques were lost generations ago. He then leads the heroes to a locked door which a previous master had sealed. Not being able to help any further, Glass' Master excitedly starts to sparring with the Hengen Muso lady. Anxious to find information to help their battle, Naofumi pushes his party towards the sealed door.

Chapter Two: Holy Tool Grotto
While at the sealed door, Shildina uses her oracle abilities to peer into the lock when she accidentally opens the door. Inside, they find the area in relatively poor condition. However, they also find a powerful fan for Glass which gives her multiple skills - including the ability to reflect debuff and nullification spells. Checking further within the room they find various equipment including a mirror for Naofumi.

After looking through the area, the group decides to experiment with their new equipment. During that time, Shildina learned that she could use her oracle powers to merge with Glass to create a more powerful form. This form will allow them to use the long forgotten skills of Glass' style and use multiple skill at once, however it rapidly consumed Glass' vital energy. Heading outside, the heroes find Glass' Master and the Hengen Muso lady completed with their battle. Everyone, including Glass' Master, then head to L'Arc's castle to train and mentor others.

Chapter Three: The Work of Men and Monsters
While Naofumi and the others were making their way to Glass' home country, the Demon Dragon was moving a transport mirror to her own domain. Naofumi and various members of his party decided to travel to the Demon Dragon's continent. During the travels, the Demon Dragon explains the magical workings of her country and how it has fallen to ruin since he was last defeated. Conversation leads to Naofumi and Raphtalia's relationship since everyone expects them to be closer. However, Naofumi is still trying to sort out his feelings for Raphtalia since he bought her as a slave and Raphtalia is respecting his time since he has been incredibly busy. As the conversation ends, they arrive at the Demon Dragon's castle.

Chapter Four: A Visit to the Demon Dragon Castle
Arriving at the Demon Dragon's castle, they find it to be in ruins. The Demon Dragon is about to summon her generals - the four heavenly kings - when they realize that they aren't alone at the castle. The newcomers meet the heroes and their leader (whom Naofumi calls Ren II) rudely ask what their business at the castle is. At the Demon Dragon's request, they only reveal that Glass is a hero. Silently, Naofumi group realizes that this group is lead by a reincarnated individual. Probing to see the newcomer's intentions, Naofumi's party splits up to search for treasure.

Chapter Five: Appraisal Camouflage
As Naofumi's group splits up, Ren II's group starts to tail Glass. Out of nowhere, one of the tailing party members attack Glass. Glass easily repels her but the party member which attacked her suddenly acts as if the attack mortally wounded her. Ren II confronts Glass and blames her for attack his party member. Even though Glass eventually apologies, the vanguard and his party start to attack her. Before the fight is about to get worse, the Demon Dragon steps in between the two groups to intervene.

Despite the Demon Dragon's attempt at negotiations, Ren II and his party attempt to attack. The Demon Dragon reveals that they know that Ren II is a reincarnated individual with the ability to appraise other's abilities. She then releases the magic which gave Ren II a false low reading of the heroes' party. Terrified of their true power, Ren II attempts to abandon his party and run away. In the end, the Demon Dragon ate them all to prevent them from reincarnating.

Chapter Six: A New Heavenly King
The heroes recover from the Demon Dragon's carnage from destroying the Vanguard of the Wave and his companions. To their horror, their corpses revived as zombies so that they can start fixing her castle. The Demon Dragon then addresses her generals who had arrived at her call. The heroes' suspicious are aroused when they hear that the generals feel the Demon Dragon's presence in "multiple place" and that one of the four general apparently resisted her call. Naofumi proposes that the enemy is attempting to experiment to make their own Demon Dragon which the Demon Dragon Emperor fragments the original demon dragon had spread around.

Frustrated at the one general who ignored her call, the Demon dragon strips her of her power and the proceeds to give it to Filo. Filo is then unwillingly transformed from a humming fairy to a heavenly king which gives her incredible powers. The demon dragon also unlocks a magic unique to her as the dragon emperor for Naofumi and the other heroes to use. The Heroes are suspicious of the Demon Dragon and her recent unilateral decision, however they progress down to the treasure room.

Chapter Seven: The Demon Dragon's Treasure
The Demon Dragon unlocks the seal and then leads the heroes into her treasure room. They find a dragon hourglass and a plant similar to the sakura lumina from Q'ten Lo. Knowing that Glass is a descendant of the extinct pacifiers within her world, they attempt to conduct the ceremony to officially make her the pacifier. Unfortunately, the ceremony is only effective when Glass and Shildina are merged. Therefore, the two must be merged in order to use pacifier abilities and authority. The heroes then continue to search throughout the treasure room.

After finding various junk items, Naofumi find ancient texts intended for Heroes. Kizuna is given a prophecy and the others are given the conditions needed to properly wield the Legendary Ofuda. There wasn't must else useful in the vault. However, the demon dragon and her four heavenly kings performed a "job change" which provides a power-up similar to a class-up.

Chapter Eight: An Alluring Pudding
The day after, Naofumi returns to cooking for a strategy meeting with all allies. Apparently, the enemy wielder of the Vassal Harpoon has started to become active so they prepare to defend against him. Naofumi gives various equipment he had made from the materials from the Demon Dragon's treasure room. With the help of the Hengen Muso lady and Glass' Master they were also able to develop the skill learned at the Holy Tool Grotto to reflect nullification magic so that all heroes could use it. However, it doesn't have a 100% success rate.

At the conclusion of the meeting, Naofumi brought out an experimental dish to try. The food provided a significant power-up but had an odd flavour and texture. When Naofumi revealed that it was blood pudding, many of the others gagged in horror, causing a commotion. However, before Naofumi could get in trouble, they got word of hostile forces heading towards L'Arc's country and the Demon Dragon's country.

Chapter Nine: Just to Make Sure
After a quick decision, they decide that L'Arc, Therese, Ethnobalt, Yomogi, Tsugumi, Itsuki, the Hengen Muso Lady, Glass' Master and Raph-chan will confront the enemies in L'Arc's country while Naofumi and the others will confront the ones in he Demon Dragon's country. Naofumi uses his Vassal Mirror skills to transport everyone to where they need to go.

When Naofumi's group arrives to the Demon Dragon's castle, they find Malty and Syne's sister. With them are three reincarnated individuals holding the Vassal Harpoon, Vassal Boat and the Legendary Ofuda and a fake Demon Dragon among them. Apparently, the reason part of the enemies forces split up to come to the Demon Dragon country is because the Vassal Harpoon wielder wanted revenge for the Demon Dragon's previous general who was recently stripped of her powers. After an initial talk, the two groups prepare to fight.

Chapter Ten: The Importance of Anger
Before the battle begins, the Demon Dragon has a serious talk to Naofumi about how he should forsake his own anger. Upon using both the Shield of Wrath and Shield of Compassion, all allies are powered-up. The battle starts. Sadeena faces off against the harpoon wielder, the Demon Dragon against the false demon dragon, Glass and Shildina against the ofuda wielder, and everyone else as support. Malty tries to use the authority of their Legendary Weapon to strip Naofumi's party of their Vassal Weapons but Kizuna's Legendary Hunting Tool prevent this from working. Naofumi's team then starts applying their buffs.

Chapter Eleven: Opposing Nullification
Now the battle had started in earnest as spells and attacks are cast in every direction. The enemy attempts to nullify Naofumi's groups buffs but their attempts are quickly rejected. Due the their teamwork and skill, Naofumi's team starts to gain the upper hand. Suddenly, as Malty was about to attack, her companion stabs her in the back.

Chapter Twelve: Intelligence Operative
Malty's "companion" turns out to be Rino, someone Malty had previous tortured just because Malty didn't like her. The battle briefly pauses as the unhinged Rino pushes Malty off the flying Vassal Boat onto the group and then repeatedly stabs her. She then takes the Vassal Whip Malty was holding. Naofumi realizes that Rino was Queen Mirellia's intelligence operative they were told about earlier. At the same time, the accessories controlling the Vassal Harpoon and Legendary Ofuda were destroyed and they chose Sadeena and Shildina and their respective wielders. Seeing that they were starting to lose, the Vassal Boat recovers Malty's soul from her now-dead body and retreats - leaving the previous weapon owners, the defeated false demon dragon and S'yne's sister behind.

Chapter Thirteen: Insensitive Individuals
The abandoned vanguards of the waves are devoured by the Demon Dragon, body and soul. The heroes quickly learn and apply the power-up methods of their new weapons to prepare to take on S'yne's sister.

Chapter Fourteen: Megido Iron Maiden
Together, all of Naofumi's group attempts to attack S'yne's sister. However, their attacks are easily repelled by their enemy. With the help of the Demon Dragon and as a last-ditch effort, Naofumi summoned the upgraded cursed skill: Megido Iron Maiden to attack S'yne's Sister. However, despite their combined power, they are hardly able to damage their target. Naofumi is barely able to hold back the retaliatory attack. However, S'yne's Sister decides to run away - cryptically saying that they'll be a good challenge in the future.

With their enemies gone or defeated, Naofumi and his group are quickly introduced to Rino and then head to the port where the rest of the heroes are fighting.

Chapter Fifteen: Defense of the Port
Arriving at the port, they see that L'Arc and the others are nearly completed cleaning up from their battle. Checking in on Itsuki, they find him with the recently defeated Mald who had confessed with his crimes but is still unrepentant. In celebration of their victory, L'Arc puts on a massive party.

Epilogue: A Visitor Late at Night
After the party, Naofumi starts to head to bed. However, on the way, he is met by S'yne's Sister who had just helped partially repair S'yne's Vassal Sewing Set. S'yne's sister reveals that S'yne has been keeping information from Naofumi in fear that he would die. She then reveals that the enemy behind the waves which Naofumi has been fighting is called the Third Army. All of the attacks so far have just been minor experiment and just a small fraction of the true force of the organization. She warns him that since he "killed" Malty, they will try to destroy Raphtalia's World. He should go back there before the Third Army's forces do.