Manifestations are exactly what they say on the package, a being made entirely out of the residual energy a person gives off of, both kinetic or magical energy. These beings can take many forms, weather it is as voices, or as animals, or even as bizarre monstrosities or humanoid beings. Every Manifestation is directly tied to a human, and their power is entirely based on how they are effecting a person physically or emotionally, as well as whether or not the person they're tied to is aware of their existence.
Manifestations usually come into existence through the build up of magical or kinetic energy, either through a person being over exposed to this sort of energy, or by developing these sorts of abilities without being aware of them. The energy will then mix with the emotions and feelings of the person and turn into a Manifestation, which will slowly grow as the person absorbs or generates more energy. Once the person becomes aware of the manifestations existence, they will begin feeling more adverse effects from it and it's progress will speed up as it becomes overwhelming to the person it is tied to.
When the person the manifestation is tied to dies, one of two things can happen. Either the manifestation will die with them, or it will attach itself to someone the person was close to, and begin feeding off them to grow stronger.
Abilities tend to differ between the different manifestations, and tend to be tied to what form they took, the emotional state of the person they're tied to, the abilities of the person they're tied to, and the way they are effecting the person physically and psychologically. These effects can range from physical pain, various ailments, and prevalence of particular emotions, as well as lead to things like hallucinations. Manifestations tend to either be neutral or malevolent beings, and tend not to care much for humans aside for the ones they are tied to and the ones who are close to the person they are tied to.