Author's Note: First off, Apologies for the late update. I will try not to make a habit of it.
An Engram is a concept of an event or an effect, or more accurately the portion of a soul based around that specific concept.
Fuel is ubiquitous, intangible, has several names, and cannot be seen or sensed without some form of magic. Any living being can sense Fuel, and most can be trained to recognize it in different concentrations
Magic is the term for the action of Binding an Engram to an object or place, Manifesting it by using Fuel, and the effects doing this has on the world. All sentient beings on record can use magic to some degree.
Death Magic is the name for the adapted form of Fuel that is created as any living being dies. Has some interesting effects, and is especially notable because it is the only thing that can allow the spirits of the dead to manifest, barring special circumstances*.
Ghosts are one term for the spirits of the dead, but are sometimes confused with death spirits in general. They can manifest anywhere there is death magic to fuel them, and they can collect death magic for later use. They can and will show up whenever they decide to, but it is draining on their collected power.
They cannot Manifest conceptual Engrams, but they can manifest physical objects, such as bodies, clothes, weapons, and fire. The power drain to manifest an object is dependent on both mass and energy.
As the objects resemble extraordinarily precise and complex telekinetic constructs more than actual matter, it requires only slightly more power to produce a two ton weight than to produce an explosion of the same force.
*If two souls have a strong, direct, link. Marriage, for example.