Well folks, I did say I was going to bring back A Betrayed Devil and so I have. If you don't know this story from my previous attempts at it, then I'll explain; It introduces my Devil OC, Damian Mammon-Lucifer, the grandson of the original Lucifer in High School DxD, and is heir to the Lucifer Clan as well as the House of Mammon, which is an Extra Demon Clan but their status updated from that after marrying into the Lucifer Clan. The backstory of Damian is he was born before the civil war and grew up alongside Sirzechs as his best friend and brother in all but blood.

Then the civil war came, Damian was on Sirzechs' side, he met Grayfia Lucifuge and they fell in love with each other. However, months after the end of the civil war, when Damian was ready to propose to Grayfia, he found her and Sirzechs in bed together. Because of this, Damian was angry and pissed off, and after a fight with Sirzechs, he left the Underworld in exile for a very, very long time and wouldn't be seen until the start of canon.

This story is a harem, with Yasaka as the main, as well as alpha girl of the harem, though it'll consist of women from other anime as well as DxD, but don't go requesting Grayfia to be in... unless it's hate-fucking which I doubt I'll do. Damian's a bit of an Anti-Hero in this, not a good guy but he ain't bad either, though he can be as dark and cruel as Devils of his bloodline. He is the grandson of Lucifer himself after all.

Disclaimer: I do not own High School DxD. I only own the OC Damian Mammon-Lucifer.


Betrayal.

One word. Three vowels. One meaning.

The dictionary definition of the word betrayal is "the breaking or violation of a presumptive contract, trust, or confidence that produces moral and psychological conflict within a relationship amongst individuals, between organizations or between individuals and organizations." The one who betrays is usually called the betrayer or traitor and is mostly universally looked on with scorn.

Arguably, the most infamous of traitors (other than Judas Iscariot) is none other than the original Lucifer himself. Once considered the most beautiful of God's archangels, Lucifer's fall began when God began favoring man over angels. This caused envy and jealousy to enter Lucifer's heart as he couldn't understand how God could favor the "hairless apes" over those he considered His greatest creations, the angels. Since then, the name Lucifer has been associated with betrayal of the highest order.

Thousands of years ago, the God of the Bible created the Angels. Now, the official definition of an angel is of an ethereal creature who assists and serves the God of the Bible. In the Christian bible, angels were portrayed as powerful and dreadful, endowed with wisdom, correct in their judgment, holy, but not infallible. When their duties were not punitive, angels were beneficent to man. When their duties were punitive, they were known as avenging angels and were mentioned in verses such as II Sam. Xxiv. 15, in which an angel annihilates thousands on God's command. These avenging angels were used by God to punish men for their sins.

Now, the important part was this: they were not infallible.

Lucifer's betrayal showed this clearly and its effects changed the scope of the Judeo-Christian religion forever. Angry at God loving Man above him, Lucifer tried to prove mankind was beneath them and created the first demon, Lilith. He thought that by corrupting her, he was proving how low Man could fall and how beneath the angels they truly were. This act was Lucifer's betrayal in God's eyes and he ordered Michael to cast Lucifer out of Heaven for all time as punishment for his actions.

Lucifer felt betrayed both by his Father's unjust (in his mind) punishment as well as his brother Michael for siding with Him. Wishing revenge for their betrayal, Lucifer created a kingdom in the part of the Chaosplasm left over from when Creation was made, where he had been banished to. This kingdom was eventually named the Underworld though it was often confused as Hell. This was due to the fact that Lucifer began creating an army of devils in the Underworld in order to eventually wage war on God for his 'betrayal'. And so was born the second Faction of the Biblical pantheon.

Lucifer then went further and transformed himself and the three fellow Fallen Angels who came with him into the first four Devils: Lucifer himself, Leviathan, Beelzebub, and Asmodeus. There, he carved his own kingdom which was a separate dimension that was the same size as Earth with the exception of having no bodies of water and a purple sky that made it perpetually twilight. The atmosphere was also made in such a way as to be toxic to pure humans.

There, in his new kingdom, which many confused with Hell, Lucifer and his fellow Devils bided their time and created more Devils. They did this by using the souls of the damned that they plucked from the section of true Hell reserved for those who followed God of the Bible's religion. The process he used to do this is lost to time but many say he got the idea from an ancient enemy of Heaven that he once fought before his Fall.

Eventually, their army grew and many Devil generals rose above the others. The 72 highest and most powerful ones eventually appeared in what is now known as the Ars Goetia of the Lesser Key of Solomon. Each Devil general had their own region of control within the Underworld, some more than others but each important in their own way to the continued survival of the Devil race.

Meanwhile, Lucifer's actions had caused a stir amongst the angels in Heaven who began to wonder how he was capable of doing that if they were supposed to be inherently good. God, fearful of his angels rebelling and causing chaos on Earth, set up the System which would eject any angel who 'sinned' from Heaven as well as turn their wings black to signify their new status. This was meant as a deterrent to stop other angels from following in Lucifer's footsteps. He thought that the threat of being ejected from Paradise would prevent them from doing something he did not wish them to.

Unfortunately, this had the opposite effect as many angels saw this as a restriction on their freedom. Why should they be so restricted when humans, God's favored beings, were not similarly restricted?

Eventually, this frustration erupted into mass rebellion led by twelve-winged angel Azazel who then became the leader of the fallen angels. These fallen angels were then organized together into the group later named the Grigori. And so was born the Third Faction of the Biblical pantheon.

And it wasn't long before war broke out between the three, a war that would come to be known... as The Great War.

The Great War lasted millennia with neither side gaining any leverage over the other. Late in the war, the Fallen Angels retreated from the fighting though the Four Great Satans (Lucifer, Leviathan, Beezlebub, and Asmodeus) and the Angels continued to fight each other.

In the final climatic battle of the Great War, the Four Satans and God fought each other. The battle lasted for days until eventually, with a tremendous explosion, it ended. From the ashes of that battle, nothing was found, showing that all Four Satans and God Himself had perished.

Knowing the effect God's death would cause, this was hidden by the higher-ups of all three sides. While a real peace wasn't established, a tentative cease-fire was formed between the three sides. The losses caused by the war made continuing it a suicidal endeavor. It would only end with all three sides dead.

For a while, things seemed peaceful. However, eventually discontent and rebellion began to grow in the Underworld. The descendants of the old Satans wished to continue the War, sure that now with God dead they could win the war. The majority of the devil population, however, did not wish to continue fighting a war that they felt had lost all meaning with the original Satans' death. This created a state of Cold War between the 72 Pillars that did not wish to continue the war and the four Satans and their supporters who did.

When the war eventually ended, each side had lost so much and left the Three Factions in a state of conflict. However, due to a state of extreme exhaustion after the Great War and with all three factions losing their main forces, inclduing God and the Four Satans, neither of the three sides wanted to continue battling. So while there was no peace between the factions, outright battles did not occur either.

Many years later and after the death of the Satans, the Underworld fell into a civil war with the Satan families wanting to continue their families legacy and fight against the Angels and the Fallen ones while on the other side were many of the remaining families of the 72 Pillars that had been reduced to now just 34 that wanted peace and a new order.

The conflict lasted for almost a decade until eventually five devils from five different families all stood together and pushed back the Old Satan Faction and secured the war in favor of the Anti-Satan faction.

Sirzechs Gremory, Ajuka Astaroth, Serafall Sitri, Falbium Glasya-Labolas and finally Damian Mammon-Lucifer, the son of Sarlith Mammon of the fomerly Extra Demon clan, now officially a noble House, Mammon and Raylix Lucifer, youngest son of Lucifer and Lilith themselves.

Though young each young devil boasted incredible raw power that left many shaking where they stood and could decimate entire countries at a time. Each with their own skills set and power, individually they were powerful but together they were near invincible.

The strongest of the group Sirzechs Gremory and Damian Mammon-Lucifer were best friends, rivals and had known each other since they were in diapers. Sirzechs with the Power of Destruction and Damian with the Primordial Power of Darkness inherited from the Lucifer Clan, as well as the ability to use Light Magic due to his grandfather's former connection to Heaven as he had been an Angel first before he became a Devil. But anyway, the two quickly became names that struck fear into the hearts of anyone that heard their names, with Damian even being nicknamed 'The Devil of Death', a slight counter to the 'Angel of Death'

The civil war had taken its toll on every Devil alive but eventually the Anti-Satan faction prevailed with Sirzechs landing the final and deciding blow to Rizervim Livan Lucifer and securing the victory for the new Devil faction.

With this the old faction retreated and hid while the Underworld quickly began to change under its new management.

With the leaders gone, the five stepped up to take responsibility of the Underworld and to protect its people and everyone that lived and breathed in their home world.

Before this could continue a problem arose, one that surprised many and shook the friendship between Sirzechs and Damian.

Despite being best friends the two had their arguments from time to time and had their own opinions on certain matters. However, many were left surprised when the very thing that caused tension between the two to rise was not a thing or an object but in fact a person.

A woman called Grayfia Lucifuge.

Grayfia was a beautiful woman from one of the Extra Demon families that was seen by many as the perfect female Devil. She had beauty, she had brains, she had power and had an attitude that could keep even the foulest of male devils in line.

She had originally been on the side of the Old Faction but after meeting the five heroes of the New Faction she defected and became a powerful ally for the new group. She quickly stood out to everyone but none more so then Damian and Sirzechs.

At first she had taken a shine to Damian and the two quickly became a couple and had spent many months together in their own bubble of love.

But while Damian had given his heart to Grayfia, her eyes and her heart was secretly yearning for another.

It was only a few weeks after the defeat of the Old faction that Damian had returned home to find his girlfriend's clothing spread across the floor along with male clothing that definitely did not belong to him and could hear voices coming from their room.

Every step he took caused bit of his heart to break off until eventually it shattered altogether when he found Grayfia in their bed with none other than his best friend Sirzechs.

What happened next led to Sirzechs almost being burned to a crisp and reduced to ashes as Damian went into a fit of rage as he attacked his now former friend.

It took the combined efforts of Damian and Sirzechs' parents along with Grayfia, Serafall, Ajuka and Falbium to eventually restrain him and stop him from killing Sirzechs. It didn't take them all long to figure out why he was angry with the state Sirzechs and Grayfia were in.

A week after the incident, Damian and Sirzechs did the only thing they could think of to resolve the problem and decide who Grayfia's heart belonged to.

They fought and what a fight it was.

The fight that made entire war look insignificant in comparison and lasted for almost three days straight with neither of the fighters giving either a moment of rest and which shook the entire Underworld to its core. Enormous parts of the Underworld had been reduced to rubble and would take years to rebuild though thankfully no one was harmed after being evacuated to somewhere safe.

After three days the victor finally emerged. That day, despite his great power, Sirzechs proved to have that extra little bit needed to win the match and Damian was defeated.

Defeated and now having to watch as his best friend spent his life with the woman that he loved.

Both wound up in the hospital due to exhaustion and injuries. Both were confined to bed rest and not to leave the bed until the doctors told them too.

It was during this time that Damian was visited by Grayfia. She told him she was sorry and that he didn't deserve to be hurt the way he did but she couldn't deny her feelings for Sirzechs anymore.

She loved Damian, he was her first love and no one ever forgot their first love. But Sirzechs was her true love and the man she knew she wanted to spend the rest of her life standing beside.

Damian made perfectly sure that she left his hospital room in tears and with a pained heart, for his rage had been so great he couldn't bear to look at her nor could he keep all the contempt within at this ultimate betrayal from the woman he loved, the one he thought would be the one he spent the rest of his eternal life with, and his brother in all but blood.

Not even waiting to be cleared or checked out by doctors, Damian snuck out of the hospital, packed his things and left. He could not stay and see the happiness between Grayfia and Sirzechs, knowing what they've done.

He told nobody where he was going, not even his family. He simply vanished without a trace, which made it clear that he wanted to be left alone.

The Underworld would never see nor hear of the Devil of Death for many, many years...


I know this was more of an exposition chapter, but it's a start to be honest and until I can figure out what I'm going to do next because I'm conflicted with two paths: One is having the story begin near DxD canon like I usually do and yet I fail spectacularly at making it interesting. The second... is to show what Damian goes through in his years of exile, how he meets Yasaka and how they fell in love, as well as her helping him move on from the pain caused by Grayfia and Sirzechs.

Let me know in the reviews, and if it's the latter... please try and help me out with story arc ideas, like the romance between Damian and Yasaka. I'm still debating what time period to begin Damian's exile, and I got a suggestion to have it begin around the time of the Mongol Invasion of Tsushima, which means the exile would begin in the 1200s.

I want to have Damian and Yasaka's romance be like the forbidden type, as well as try and set it like the mysterious warrior meeting the beautiful princess trope you see in films set in Feudal Japan or something like that. With Yasaka being princess of the Youkai Faction and her father the leader of it.

I'm also thinking of adding Celestine and Olga from Kuroinu into Damian's harem, but I need ideas for how he meets them as well as an arc that can develop that relationship.

Seriously, people, try and help me out here.

As for the harem, or at least the ladies in it so far...

Harem: Yasaka (Alpha and main girl), Kuroka, Serafall.