Thanatos Arc

**Thanatos Arc** is the eighth and (seemly) last story arc of Masō Gakuen HxH series featuring Thanatos, the last goddess of the four Goddess of Deus Ex Machina. With the defeats of Hokuto, Osiris and Odin, Kizuna and his allies must defeat the last Machine God so they can save both Earth and Vatlantis from their annihilation. However, the risk of doing so would actually speeding all worlds' destruction since Thanatos herself is both the creator and enforcer of her own rules that also responsible to all worlds' existence.

## Plot

### Secrets of Thanatos's Immortality

#### Part 1

Due to the extensive damages of Battle Ataraxia and Golden Dragon, everyone including Odin have to travel via Battleship Oldium. As Nayuta is drinking her tea while recuperating from her wounds, courtesy to some of Odin's powers, Kizuna and Reiri are sitting besides their mother with the former begin to wonder his own feelings towards his parent even after all of her wrongdoings, while the latter still belittling against her.

### **Kizauna's "Death" and Defeat**

Just as he is about to warn everyone, Kizuna suddenly finds himself alone at Thanatos Temple and confront the last Goddess herself. In their confrontation, Thanatos laments her "failed experiments" regarding the mortals' evolution after witnessing her fellow Goddesses' defeat. Sympathizing Thanatos's melancholy, Kizuna requests Thanatos to let the "failed experiments" live but Thanatos, believing the current events will bring unpredictable influence, decides to erase everything and going to purge her former allies. Kizuna then attacks Thanatos but no matter how much he tries, even with various Modes that destroying Thanatos Temple, Thanatos remains untouched until her amour is shattered by Kizuna's Mode Zeros however, to her shock.

Kizuna then warns Thanatos to leave both Earth and Vatlantis alone, but the latter refuses, forcing Kizuna to retaliate. Just as Kizuna moves forward and tries to land his hot onto Thanatos, he notices something at Thanatos's back that leads to his assumption that she is either attempting to escape or sending him to another world. However, in his attempt to capture Thanatos while dodging her attacks, Kizuna is shocked to see Aine of all people appears in front of both him and Thanatos. Unbeknownst to either Kizuna or Aine, Thanatos uses their confusion to attack Kizuna through her sword that causes a huge hole at Kizuna's torso. Feeling confused and anxious over Kizuna's bloody conditions on her arms, all Aine can do is helplessly calling his name while crying and hugging his corpse. Thanatos then asks Aine about Kizuna's action, but after witnessing her sadness, she opts to ask someone else by opening an Entrance that brings Reiri to the scene.

Reiri rushes towards Thanatos and attacks her, but the latter vanishes instead. Regardless, Reiri checks on Kizuna but she is mortified to realize his lifeless condition. Later, more Entrances appear and this time it's the members of the Earth-Vatlantis Alliance (Himekawa, Yurishia, Sylvia, Gravel, Hyakurath, and Grace) and they too are horrified to see this condition. Thanatos later reappears and whilst facing Reiri's hostility as her sword pointing at the Last Goddess, she asks everyone about Kizuna as she fails to comprehend his sacrifice for Aine despite his higher combat prowess. Aine is shaken by Thanatos's words to the point her body convulsing from terror and guilt and blames herself for Kizuna's death, though Grace still refuses to give up and tries to snap her sister out from despair.

Intrigued by Airi's grief, Thanatos then asks her about her sadness but Yurishia begins to aim at Thanatos while telling Grace and Hyakurath to take care of Kizuna and Aine, all to avenge Kizuna.As Hayuru and Silvia are ready to join the fray, Reiri roars her battle cry that signifying their battle against the Last Goddess.

### **Earth-Vatlantis Alliance vs. Thanatos**

Reiri firstly engages with Thanatos in a sword fight whereas she cusses to the Goddess and vows to exterminate her  until not even single cell remains behind. Further intrigued by the sudden change of phenomenon from death, Thanatos mutters about killing everyone so she can get more data about them. Gravel and Silvia are next to attack Thanatos but none of their attack works, as Thanatos explains that this world's physic laws follows her will and their weapons are merely light particles converted from magic power while drawing her own sword.

Yurisia and Hayuru then activate their respective Corruption Armament and charge towards Thantos and attack her, only to be horrified to see their Corruption Armaments are broken instead. After explaining the changes of physics, Thanatos sends them flying by shattering both Cross and Neros with her sword. Gravel and Silvia then seize this moments to attack Thanatos, but the Goddess disappears and beaten them by destroying their weaponry that causes explosions.

Reiri then tries to attack Thanatos from behind but her sword is pulverized before it even landed on Thanatos due to the changing physic. This allows Thanatos to slash Reiri that partially breaks her Zeros. In spite of Zeros' broken armor, Reiri refuses to give in but Thanatos claims their resistance as futile as she explains that only machine god can match her prowess and planning to kill Reiri next in order to witness the influence of the human's death to everyone. This prompts Reiri to experience despair as she thinks about her helplessness to see her brother's death while calling out Nayuta out of desperation.

### **Rouge Goddesses' Rescue**

#### Part 1

Suddenly, a familiar voice snaps Reiri back to reality and to everyone's (including Thanatos) astonishment, that voice belongs to Odin who opts to help them as her means in fulfilling her promise. Thanatos then shot Odin with her blast, though it is deflected by Odin's Gungnir. While she is "impressed" by Odin's Gungnir, she warns Odin that she is no match against her due to her and her world's fragile state. Odin however retorts that she will not let Thanatos have her way and even Thanatos asks her to whom she made her promise, Odin only smiles and not reveal any word.

Odin then asks everyone about Kizuna's condition, but before anybody can even answer her, Osiris arrives and uses her light to surround both Aine and Kizuna, much to Yurishia's surprise. Osiris then checks on Kizuna and finds that his soul is still lost, leaving Odin to cover Osiris while fighting against Thanatos at the same time.

## Epilogue

### **Rebuilding World**

The following aftermath of Thanatos's defeat and Entrances'disappearance, the Earth is saved and people across the world are celebrating its returning peace and society begins to slowly rebuilding itself. Despite this, however, this celebration is short-lived as some are seizing this opportunity to fulfill their ambitions-mostly motivated by their greed-by creating new countries and waging war against each other for total domination. Ataraxia became the main target for every countries and groups over the world for their overwhelming technology and powerful Heart Hybrid Gear pilots, despite them being heroes who saved the world from various threats.

In the present day, Kizuna is doing Ecstasy Hybrid with Yurishia inside the Space Love Room for a mission. After finishing climaxing with Yurishia, the two head out to destroy the 24 ICBMs missiles that were targeting Ataraxia. Believing that the reason why Yurishia wanted to do Ecstasy Hybrid was to deal with the attack without increasing the debris, Kizuna compliment's her for thinking about her juniors, which wasn't actually true. While Yurishia lies that that was what she was thinking, Scarlet cuts in and points out it just an excuse to do Ecstasy Hybrid with Kizuna. Yurishia argues against Scarlet's accusation and decides to return back with Kizuna.

After returning to Ataraxia, Hayuru comes to pick up Yurishia and Kizuna in a electric car. However, Kizuna had already left by the time Hayuru gets to Nayuta Lab. While driving, Hayuru tries to lecture Yurishia on how she didn't need to do Ecstasy Hybrid early, only for the latter to point out she also did it during the attack on a nuclear facility the week before. Through deeply embarrassed, Hayuru doesn't deny that she did it. Yurishia points that their doing Ecstasy Hybrid is not only for missions, but also for the sake of safety ejecting their core's so they can be passed onto the next generation, as Nayuta isn't around with them anymore.While fully understanding what Yurishia is saying, Hayuru still feels conflicted about making children with Kizuna since he and Aine are officially together, but can't let go her own feelings for him even Aine said she is fine with it.

Unfazed by this, Yurishia points out that they don't need to feel bound by the laws of old world since Ataraxia is currently an independent country and has been thinking about making polygamy legal. They soon arrived at the dormitory to see Aine welcoming them. After talking about their respected missions went, Hayuru brings up how Yurishia wanted to make polygamy legal. Aine is completely fine with this, as she calls it the composure of the legal wife (referring to herself), through Yurishia point's out that the first to get pregnant with Kizunas' child will be in the lead. Hearing this, Aine brings how the commander, Reiri Hida, might have the biggest advantage over them, having heared a rumor that she been abusing her authority to summon Kizuna whenever he has free time. The three then become determent to find out from Kizuna whether or not this is true.

### **Setsuna Hida**

The scene change to the practice class for the elementary school where Gertude Beard is currently teaching as Kizuna watch's. The children are amazed to meet Gertude, due to fame as "the Godslayer", which she puts down by pointing out how she didn't defeat a god by herself. One of the students named Setsuna Hida asks Gertude if there is any point in training since they don't if know any of them will become strong in the future, something the other students are worried about as well. Fully understanding the children worries since she felt the same way herself, Gertude agrees that they might not become even pilot, but tell them it doesn't matter if they don't. She tells them it how they live is what will decide their value as a person, and they just need to find where can be most useful.

After finishing her speech, Gertude has the children start training as she goes talk Kizuna. The two start talking about he is worried about Hida Setsuna, who is publicly considered Kizuna's little sister, but is actually the result of Thanatos consciousness being transferred into the body of Hida Nayuta after she replaced the former as the god who rules all worlds. Gertude then brings up that they're going to start training with the Technical Gear and ask's Kizuna if he can be Setsuna training partner because of his past experience with it. Through Kizuna agrees to try, he suddenly told by Valdy, who is currently Reiri bodyguard, that his older sister is calling for him. Understanding why his older sister calling him, he agrees to go but Valdy forcefully carries him to fulfill her orders, much to Gertude's amusement.

In the command room, Reiri is having a speaker conference with the leaders of various countries. She brings up the earlier ICBM missiles attack and that within four months they will remove the nuclear weapons of the country responsible. One of the leaders takes offence to this, but Reiri just tells them that schemes and bargains won't work in Ataraxia and that they should start worrying about the countries surrounding them after their nuclear weaponry gets removed. Growing enraged by Reiri, the voice on the line threatens that they will sink Atarxia before that happens, even bring up their country's Heart Hybrid Gear. However, Reiri just mocks them to send attack them with their Heart Hybrid Gears, as it will make it easier for them to steal the cores for themselves. This remark causes the voice on he line to Reiri a demon, which she mockingly points out is true.

Reiri is about bring up how one of the country's has been trying to spy on them with a unmanned drone before she suddenly pause mid sentence, confusing all the country leaders. She quickly decides to end the conference and cut off the communication with them before they could rebuttal. The second the communication is cut, she releases a coquettish voice, revealing that she was doing Ecstasy Hybrid with Kizuna the whole time, which was the reason why she called him. Even when the conference started mid way through, Reiri didn't stop but simply had Kizuna pause with his *thing* still inside Reiri. While Kizuna suggested they should've stop temporarily, he couldn't argue with her that it was exciting, which is why Reiri almost let out her voice when his thing got bigger inside her.

The work now over, the two get back to what they were doing, with Kizuna not holding back anymore, much to Reiri happiness. After finishing, Reiri kiss's her younger brother before wishing to continue some more. Through Kizuna tell her she doesn't need to be so greed, Reiri simply tell him she wants to let their mother see her grandchild. Recalling the small time they sat peacefully together as a family, Kizuna wonders if their mother can see them. Reiri gently reminds him that Nayuta is now the god who manage all world, so she probably can see them. Happy with this, the Hida siblings continue doing Ecstasy Hybrid until night time.

After finally finishing and being exhaustion from doing Ecstasy Hybrid with his older sister for hours, Kizuna returns to the dormitory to find Aine, Hayuru and Yurishia wanting for him in their pajamas. The three women begin question him about what he was doing until so late at night, becoming more intense after he tells them he was with his sister. They begin demanding for more details about what the two were doing since they heard he was favoring the commander more than them. Before they can, Sylvia energetically comes through the door after returning from London. After telling Kizuna how her parents are safe, she ask what everyone is doing. Yurishia tell the young girl their going to be having a eros party with Kizuna until morning. Understanding this, Sylvia declares that she will also participate as she wants to show her parents the face of their grandchild. Not expecting this development, Yurishia try's to stop her but fail as Sylvia is determent to start now since it will likely take 5 to 10 years on average before she pregnant. This situation quickly grows worse as the girls all start arguing over who goes first until they decide to settle things with a fight using their Heart Hybrid Gears, much to Kizuna annoyance as prepares to stop them.

## Characters

### Major characters

* Hida Kizuna
* Chidorigafuchi Aine
* Thanatos
* Mercuria

### Supporting Characters

* Odin
* Osiris
* Hokuto
* Valdy

## Notes

1. ↑ Even though she didn't know what had happened, Grace knows that her sister will go to succumb to despair if she doesn't keep her optimism.
2. ↑ Of all the battles she has participated, Yurishia is often seen calm regardless the battle situation. The "death" of Kizuna seemly triggers Yurishia's rage to the point vowing to kill Thanatos, so she can avenge his late lover.
3. ↑ Originally, Reiri and others heeded the advises from Odin and Nayuta that killing Thanatos will only bring unwanted consequences. Kizuna's death however immediately changed her mind as she focuses on avenging her dead brother.
4. ↑ The first thing Odin to say to Reiri is that she refused to believe a person who has defeated her to be on her knees onto her fate. In fact, Odin and her fellow Goddesses' betrayal against Thanatos seemly becoming everyone's hope spot in reviving Kizuna.