Setting Details

[Lina Inverse]

Here is a crude but lovingly hand-drawn map of the the Slayers world. The continent this takes place on is roughly the size of Europe. Notable cities/areas are noted with red stars.

[Lina Inverse]

Cities and Kingdoms of Note
This would all be common knowledge unless your character lives under a rock and doesn't interact with humans much at all.

Atlas City - Atlas City is most known for the home of the Sorcerer's Guild currently run by Halcyform the White, an enigmatic man who's rumored to actually be an Aasimar, or even a dragon. None of these rumors have much basis, but there is something otherworldly about him. Atlas City is also a major trade hub, has lots of fine dining options, and is also an easy place to find work, as there's always nobles feuding and looking to get the upper hand over one another.

Sairaag - Often foggy and known somewhat ominously as "The City of Ghosts," Sairaag is perhaps the oldest city in all of the land. It once housed the Sorcerer's Guild, but it has long since been moved to Atlas City. Now it has become known for more... eccentric branches of magic. The most prominent feature of Sairaag is a massive, and I mean MASSIVE tree called Flagoon on the edge of the city that shades almost half the city in its branches. On the other side of the tree are the ruins of the old Sairaag which was destroyed hundreds of years ago due to a monster named Zanafar.

Sayrune - Sayrune is famous for one thing almost exclusively: White magic (divine magic in Pathfinder terms). And oh, are they zealous about it. They are full on The Kingdom of Lawful Good. The roads in the capital city are shaped like a hexagram, they're so into it. Because of this and other magic wards in the city, destructive types of magic are weakened while healing magic is strengthened. They house the biggest library in the land, have a warmer climate than many of the surrounding kingdoms, and boast the best soft-serve ice cream in the world.

Gyria City - The most militaristic and warmongering city, Gyria seems bent on claiming more of the Kataart Mountains for the Kingdom of Dils. No one is quite sure why exactly; Sure, driving the Lesser Demons that occasionally hit town from that direction out might be nice, but the Kataart Mountains are cold, treacherous, inhospitable, and full of dragons. What could they possibly want up there? Maybe there's just too many dwarves in their army.

Dragon's Peak - Dragon's Peak is -- are you ready for it? -- full of dragons. It's also the only place where the Aasimar live in a community, whom the dragons seem to tolerate.

Kataart Mountains - Once known as a holy land where Aqualord Lagradia, the Dragon of the North once lived, it is now viewed as generally terrible place to be. Not only is it cold and rocky and miserable, it probably has the most concentrated population of monsters around.

[Lina Inverse]

The Mythology and Religion of the Slayers Universe Part 1 -- Common knowledge

Unless your character has been raised without much contact with the world at large or never paid attention and got terrible grades in school, they should know most of this stuff.

The Creation Legend
In the beginning, all of existence was a shining golden sea of chaos. Then without warning, four pillars shot up from the sea of chaos, and at the top of each pillar a world formed. It is unknown how much time passed before or after this, or if time was even a concept or function yet. At some point, though, life began to appear in these worlds; powerful, incomprehensible lifeforms. In this world, the two beings that came to exist were Flare Dragon Ceipheed and Ruby-Eye Shabranigdu. Ceipheed liked the new world that had been created and sought to protect and care for it. Shabranigdu thought the new world was a freak accident; an ugly abomination that should be returned to the Sea of Chaos. And so, as the lands grew, as more and more lifeforms came to be and lived in this world, they fought. But no matter how hard they fought, they could seemingly get nowhere. They were two equally powerful sides of the same coin.

Flare Dragon Ceipheed
Ruby Eye Shabranigdu

Ceipheed bet everything on a final attack strategy. Using all of its energy, it shattered Shabranigdu into seven pieces and scattered them into the world. But that wasn't all of Ceipheed's plan: To force Shabranigdu to appreciate this world's life, its soul was sealed inside the intelligent races. The shattered soul of Shabranigdu would be forced to live and die and be reborn for all eternity in the hearts of those who lived in the gray that existed between the two forces. But this took all of Ceipheed's power to accomplish, and when it was done, it was broken into four pieces that flew to the edges of the world while the rest of Ceipheed fell into the Sea of Chaos. Those four pieces became the Dragon Kings: Aqua Lord Lagradia of the north, Fire Lord Vrabazard of the east, Air Lord Valwin of the south, and Earthlord Rangort of the west. This also caused such a massive explosion that the entire continent was shattered and it left a huge crater (roughly the size of the Atlantic Ocean) in the middle of the world that filled with water and is known as the Demon Sea.

Continent before
Continent after

Since this story takes place in what is agreed to be the north-east corner of the land, Aqua Lord Lagradia is the most commonly worshipped Dragon King, followed by Fire Lord Vrabazard.

[Lina Inverse]

The Kōma War, also known as The War of the Monster's Fall

About 1000 years ago, there was a large scale war in the north amongst many kingdoms and people. It was during this war that one of the shards of Shabranigdu consumed its human host’s soul and began the most terrible war the world had ever seen. What had started as simple warring kingdoms became a war between the shinzoku — holy dragon clans created by Ceipheed who served the Dragon Kings — and the mazoku, the twisted eldritch abominations created by Shabranigdu who served him and his five generals. The mortal creatures of the realm were no match for these two opposing forces, and were slaughtered by the millions.

Aqua Lord Lagradia and the shard of Shabranigdu

The war ended when when Aqua Lord Ragradia managed to trap the shard of Shabranigdu, whom came to be known as the Demon King of the North, in the Kataart mountains inside a glacier, then sealed him in deep, deep, in the mountains (He’s like an ice Balrog now). No one knows exactly where, but to this day there are many more mazoku and lesser demons in the area, likely drawn to Shabranigdu’s evil energy. But doing this took all of Aqua Lord Lagradia’s power, and she was seemingly destroyed, although her energy still seems to remain in places.

The Demon King of the North sealed in ice