That's very close. The phantoms are souls which Hell has given form, for the purpose of exterminating all unworthy, regarding their particular sin.
Heaven doesn't allow souls to be resurrected, as they're returned to nothingness when their vessel expires.
There are a few circumstances where souls survive this, the main cause being pure accident. Occasionally, a soul's binding to the physical world is incorrectly placed, and so something like an artifact is created when they die. Could be a rock or something, but it has a will of its own, even if it can't move.
As a summary of how Hell came across them, around 1344 NE five souls and an immortal were gathered by A.O.F Inc. in order to create a perfect weapon. Having researched heavily into the workings of metaphysical space manipulation, they create the Seven Pillars of Sin: A weapon that uses six soul-bound magical artifacts and a magically bound human to allow the powers and rage of seven souls to exist in one physical location. (This is a gameplay gimmick originally, you're that human and so you can switch playstyles with this. Unfortunately I never actually made the game surrounding that lore.
)
Anyway, six of the eight phantoms are those souls, and two are created by Hell's existence.
The eight phantoms are:
Hell - Gula
Hell itself is one of the 8 phantoms, an all-consuming realm that feeds off of the sinful.
It manifests in Lithium's universe to consume the sins of man.
Kirika - Luxuria
A formless, eternal soul that can take physical form under certain circumstances.
They were a scientist in an unknown dimension, and through the use of magic, became immortal. In Earth's time, it would be around 4th century BCE.
If they were in Lithium, they would be a re-manifestation of their previous body.
They are a pacifist, but they do know how to use a sword when they have to fight.
Makarov - Avaritia
Orphaned at birth, a Russian-born solo mercenary and murderer.
Burned the orphanage they grew up in, which also burned his eyes and a lot of his body, causing him to be blind.
Wields a shotgun, a long strap of grenades, a scythe and a chain (which doubles as a strap for his shotgun.)
Born 2804 CE, became a sinner's soul having died with regrets that he didn't have enough presence in the world; having thrown away and been thrown away by everyone.
Isaac Robinson and Mike Robinson - Superbia
Gangster brothers from America. Isaac uses a M1912 and Mike is a berserker wielding his fists and a knife.
They were infamous around 2039 CE, and along with their top man became a merged soul.
Lily Sawyer - Tristitia
Drafted during the height of the Vietnam war. Came back home to find her father dead and her mother demented.
Likes rifles, is usually bored and near the end of her life somewhat schizophrenic.
Robert Drench - Ira
Serial killer and rapist, said to have over 200 victims. A terrorist at heart and eventually also weapons trafficker.
Most famous around 2107 CE or so. Lived a long life with no regrets.
James Vagany - Vanagloria
Blood relative of Lily Sawyer, though they never knew of eachother's existence. His father and only link to her left before his birth.
Raised by a truly evil mother, became a drug addict and insane killer.
After murdering his mother, he came to the beleif that he was an angel sent to remove evil from the earth.
Icon of Sin - Acedia
The punisher of those who sin in Hell, however useless a task and essentially just a title. Destroys everything when awake, creates evil when asleep.
