The hellion is a master of dark energies, especially afflictions and hexes, who draws his power from deals cut with one or more supernatural patrons. In many ways the hellion is a more martial version of the witch, sharing the witch's power to draw on hexes and spells but with significantly more options (and inclination) to damage foes directly. What hellions give up in terms of more powerful hexes and spells they make up in greater skill in combat and special powers that have more stopping power than most witch abilities.
Hellions are often feared and hated by those who see them as universally evil and vicious. In all fairness, the powers of hellions do lend themselves to causing pain and misery, and many are just as cruel and spiteful as common wisdom suggests. But there is nothing in a hellion's powers that intrinsically requires them to be malevolent or vile. A few strive to use their powers only to punish the wicked, while a much smaller fraction actively wish to avoid causing injury, but are burdened with the powers to do so as a result of deals made during a troubled youth.
Though good and noble hellions are rare (and even the most saintly tend to appear brutal and sadistic to a casual observer when accessing his powers for the defense of others), a few do exist. Many are driven by a desire to atone for deeds done when the hellion was younger, and more prone to lash out without considering the consequences or morality of his actions. Of course such hellions are often met with suspicion and bias, and more than one has become so angry at this injustice as to eventually slide back into a life of debauchery and violence.
Role: The role of a hellion is to deal damage to foes and reduce their effectiveness through the use of hexes and afflictions, but exactly how this is accomplished depends heavily on what options the hellion chooses. A hellion of a patron of bloodshed, who takes a scimitar as a bonded item, and chooses the metal fetish talent, is likely to serve as a secondary melee combatant supporting a more heavily armored front-line weapon wielder. A hellion of a patron of curses, who takes a wand as a bonded object, and takes the master of damnations talent, is more likely to avoid the front line and work to curse foes with spells to make them easier for his allies to defeat.