Ok, I don't know really where to start, but here goes.

I have a (rather old) campaign setting me and a few friends are playing, but I want to start writing stories of my own about them. I want t to focus on a knightly order that I created. It's called the Knightly Order of the Good Death; basically it's an order dedicated to the defense of the city-states against the undead, which sprung up from the deep of the bogs, in a continent considered cursed.

The continent (save from the rich coastal cities in the west) is mostly grimm, most people are suspicious of strangers and gallows humor is common. The Knights themselves are grimm, more faithful to the cold of steel than the prayers to the gods, but it is said their oath protects their spirits and bodies from being rising as undead... Or brought to life by clerics.

I've been wanting to do a story about a group of knights of this order (initiates, and a single proven knight), but I can't really get into the mood, since I want it to be a fantasy horror story.

I simply need some pointers and inspiration for the story, which should let it flow into the right direction.