High School D×D: Goddess Resurrection

"A war between Heaven and Hell tore the World asunder... Who can we pray to? There are only demons and fiends here."

- Tagline High School D×D: Goddess Resurrection is an original story that draws heavily from the Shin Megami Tensei series. It is set in an alternate universe where an unknown entity tears the world apart, and crunches it up into three different landmasses. The Devils are now monstrous beasts best known as Demons, and the Angels are presented as amoral, strict, yet ever abiding by the laws of heaven, and the Gods either act out of personal gain or simply act out of boredom. Humanity is sitting in between the battle, whilst trying to figure out the cause behind "The Great Fall" and how to stop the Demons. Meanwhile, Issei Hyoudou wakes up to this mysterious world...after 100 years have passed.

Description
"Then Issei Hyoudou woke up, it was a hundred years later. His world was now in crumbles, in the hands of creatures that called themselves "demons." Now he must survive in this hell, whether he wants to or not. Pros, there's a cute girl. Cons, she REALLY doesn't like him."

Background Information
As stated above, the story draws heavily from the SMT franchise, which is notable for its themes of Law, Chaos, and Neutrality. Because of this, the story is more an 'inspiration AU' rather than an actual crossover. While some of the original cast from DxD will still be present with their characters intact, most of the characters will be different from how they appeared in the original work of DxD.

At an unspecified time, the world became warped and crunched up together. The entirety of Earth changed from a single sphere to three gigantic landmasses floating in azure skies, which are occupied by different factions. The Demons control the leftmost landmass, known as Purgatorio, which has the major cities and architechture of the United States, China, and Russia. The Angels control the rightmost landmass, called Millennium, which composes of Australia, Canada, and Antarctica. Humanity, meanwhile, controls the center landmass called "Valhalla." It is comprised of Japan and the United Kingdom.

Purgatorio can be considered the ruined version of hell; buildings are destroyed, fire cracks up from the ground, chaos reigning, and any human who live there are constantly being hunted for sport or boredom, forcing them to live underground. The ruling hierarchy is the 72 Demons, though surpassing them are the Three Demon Lords; Beelzebub, Leviathan, and Asmodaeus. Unknown to many, however, Purgatorio is the midst of a civil war with another group of demons who want to establish peace and order among demon kind and seek coexistence with humanity, known as the Fell Satanael Order, and led by the Fallen Morning Star Lucifer, and seconded by the matriarch of Gremory, Rias.

Millennium is referred to as a "paradise and dictatorship merged into a beautiful yet horrifying display," as in contrast, the entire kingdom is perfection and seemingly made of silver. On the surface, the humans who live there enjoy the peaceful way of life given to them, able to carry out their lives without worry and return to the life they had before the Great Fall. In reality, however, the Archangels Uriel and Raphael impose a religious rule over them and force them to abide by their wills. Any human who dares to disobey them are executed immediately. Carrying out their orders are the Messiah's Order, which is led by Dulio Gesualdo, and seconded by Xenovia Quarta. That being said, both Dulio and Xenovia have doubts about this being the proper course of action and want to change Millennium for a better system, a sentiment shared by the other two Archangels Michael and Gabriel.

Valhalla, the last of the three landmasses, is the home of humanity, and protected by Gods who love humanity for one reason or another. The cityscape is entirely covered by nature; most of the streets are submerged with water, and buildings have been covered by vegetation, as if nature has taken over. Of course, this leaves no shortage of food, as some humans have taken to farming. Valhalla is also home to the sole faction of humanity; the New World Order, which is led by Cao Cao. Seeking to free humanity from the tyranny of both Demons and Angels, the New World Order fights on both fronts. It is protected by many Gods, the most prominent being Odin, who governs Valhalla and welcomes all who seek refuge from the war. One of the most notable members of the New World Order is Leot, a female soldier who fights under orders from Cao Cao.

Aside from the three factions, a neutral individual exists in the war; Azazel. Though he is a demon, he like those of the Fell Satanael, has managed to retain his logic and reason and primarily stays in human form. He runs a night club called "Grigori's Pad," which provides information for those who are willing to pay for it, regardless of the method.

Issei Hyoudou will join the New World Order, though his journey would lead to him to interacting with both Lucifer (Sirzechs) and Rias, and Dulio and Xenovia, hence forcing him to choose a side.

According to the author, the Fell Satanael Order would be a more tame, lesser version of Chaos, the Messiah's Order would be the Law version with a touch of Chaos, and the New World Order would be a cross between the two. There is a 'neutral' path, though no details have been stated.

Changes
The World of DxD: The mythos of the light novels has been changed drastically, so much so that the Great War had never occurred, due to Azazel stating that back then, none of the supernatural creatures ever held the power they did now, implying that the Great Fall had not only changed the world, but also granted every supernatural being great power. It also explains why the Demons have become so cruel and brutal; they have become drunk on power and revel in it.

The Characters: Many characters from the main cast are either human or Demon, but otherwise remain the same. However, some characters have changed drastically; the Three of the Four Great Maous have become monstrous and tyrannic beasts who do as they please, even killing fellow demons for the fun of it. The Angels are far more strict and religious, comparable to that of zealots and fanatics. They take even the slightest act of disobedience as treason and heresy against the Lord's wish. Meanwhile, the Gods act on their own whims and reasons. Odin seems to be the only one to be different, holding a high opinion of humanity, especially when they rally under the banner of the New World Order.

The Demons: Not to be confused with the Devils fans of DxD are familiar with. Due to the Great Fall, Demons have become drunk and overwhelmed and thrilled by the power they have gained. While some take on human form, retaining their logic and more reasonable self, others have thrown away that. Their current forms are comparable to those of Stray Devils; monstrous abominations.

New World Order

 * Issei Hyoudou - the male protagonist of the story. While initially siding with the New World Order, he would join other factions in order to change the status quo between the three lands. He is the holder of the Sacred Gear, Boosted Gear. He's...also a hardcore pervert.
 * Leot - the female protagonist of the story. A member of the New World Order, she is extremely loyal to Cao Cao. Though she initially holds a low opinion of Issei, subsequent adventures in the other landmasses would lead to her coming to trust him. She is the holder of the Sacred Gear, Divine Dividing.
 * Cao Cao - the leader of the New World Order, and Odin's second-in-command. Though young, he is incredibly charismatic, and since becoming leader of the NWO, his influence has only grown. He represents a cross between Chaos and Law.
 * Odin - the ruler of Valhalla, and the representative of humanity. Unknown to many, he takes on a human guise to observe them in order to better understand humanity. He holds a high opinion of warriors, and thus is willing to aid them when they decide to fight against the Demons and Angels. That said, he tends to have a slight perversity around his trusted warrior, Rossweisse.

The Demons

 * The 72 Demons - the nobility of Purgatorio. Only bearing this rank in name only, even they are but mere subordinates to the Demon Lords. While many are loyal to them, some side with the Fell Sataenael Order, such as the Baels, Sitris, and Gremorys.
 * Demon Lords - the three ruling demons of Purgatorio. Powerful, brutal, and heartless, they act as they please and slaughter humans, Angels, and even Demons for pleasure and sports. The author has stated that they are not Ajuka, Falbium, or Serafall.

Fell Satanael Order

 * Lucifer - the Sirzechs of the story, and leader of the FSO. Powerful, strong, and charismatic, he and few others have managed to retain their sanity and logic since the Great Fall. Once known as the Fallen Morning Star, he harbors a deep resentment towards God, but doesn't want this conflict to continue, seeking to obtain peace between humanity and demons.
 * Rias - the right-hand woman of Sirzechs, and the second-in-command of the Fell Satanael Order. A beautiful woman, and also the matriarch of the House of Gremory, she is the one who helps Issei understand that not all demons have become monsters. She represents Chaos.

The Angels

 * Uriel and Raphael - twin angels who have established an unquestionable rule over Millennium. Considered to be religious dictators, any act of disobedience is the same as heresy to them, and will not hesitate for their deaths.

Messiah's Order

 * Dulio Gesualdo - the leader and commander of the Messiah's Order. Though he is a jokester at heart, he is deeply troubled by the current order in Millennium. He is the older of the Sacred Gear, Zenith's Tempest. He is also the lover of Gabriel.
 * Xenovia Quarta - Dulio's lieutenant, and the successor to Vasco Strada, and thus became the wielder of the Holy Sword Durandeel. Though she, originally, strongly believed in Uriel and Raphael, her meeting with Issei and Leot shook her ideals, leading to her and Dulio to work with Michael and Gabriel to defeat the current leaders. She represents Law.
 * Michael and Gabriel - twin angels who rejected the position of ruling Millennium, believing that Uriel and Raphael were no longer the siblings they once knew. Though they initially planned on keeping out of the conflict, their encounter with Issei led to them deciding to overthrow Uriel and Raphael with the Messiah's Order.

Neutral/Independent

 * Loki - a Norse God who acts as he pleases. He takes a great interest in the conflict between the three Lands when Issei's interactions with the factions changes the fate of the world.
 * Azazel - a Demon who owns the night club "Grigori's Pad." Serves as an information broker to anyone willing to pay for it, be it in favors or 'other ways.' Like Loki, he takes an interest in the events in the world when Issei's meetings with the three Lands begins to shape the outcome.
 * Leot - the female protagonist of the story. Initially holding a low opinion of Issei, her time with him has led her to develop a strong bond with him. As a result, she sides with him, no matter which path she chooses. She is the holder of the Sacred Gear, Divine Dividing.

Trivia

 * The main theme of the story is "renewal begins through destruction," and is considered to be far more dark while still holding the ecchi and humorous tones High School DxD was known for.