The Dark planet
On a particular planet, when one would look up at the sky, they would discover the fact that they were three moons, two of the moons shined brightly allowing a light glow on the surface. While one of the moons had an important role. It created a permanent eclipse blocking out the sun.
While the other two were naturally made, this one was not. Set up to perfectly move along and shift with the planet's slow rotation to make it so it would always remain in the dark but still would provide enough heat for survival.
This was the planet that the vampires had chosen to call home. It wasn't a very large planet, and most of the place was unpopulated, but in one section there were signs of civilization as life could be seen. Buildings created from a black hard substance crafted in a jagged style, but signs of modern technology could also be seen in use. As lights lit up the streets with a lukewarm glow, not too bright.