INNER WORKINGS: Life and Death are the cups on a scale and have the power to add as much weight as possible whenever they want. Reality is the automatically adjusting AI that attempts to balance out the weight. Fate would be an outside force, or a free hand, that can forcefully alter the weights or the AI directly. Though it's a rare occurrence since it means one of the other mechanisms to the grand scale of existence is out of order/ slip up.
*Big G would be the thing who provided the schematics that led to the invention of the scales and the theoretical designer behind the AI. As well as the thing who gave the hand an impulse to move the scales or mess with the AI.
*They are not traditional GODS [Like the Indian, Greek, Norse, Egyptian, etc. Pantheons nor is Big G some stand in for Monotheistic depictions of a singular God. They do hold ELEMENTS very similar to depictions in that they are all seeing and all-powerful. Their power and influence are vastly limited to an extent since they hard balance and limit each other.
*In this sense, they are each "MANAGERS", being more along the lines of superior beings. Similar to the "Gods" of the Lovecraftian mythos.
GOD [Big G]- An amalgamation of all things in and out of thought. Which includes things in and out of conceivable time. Meaning every pantheon, singular god, deity, or higher power cosmic or alien in the past, present, future, and (?), are all mere aspects of this thing.. (There's another frame of time I'm not allowed to translate. Sorry). But essentially, Big g is the comical depiction of the super steroid version of what "God" is. It is supposed to lead the other four Gods but generally, it "LETS THEM DO WHATEVER THEY WANT AS LONG AS EVERYTHING IS RUN PROPERLY. Including the stuff inside of Nonexistence, let's not forget what never and can't exist..
LIFE ["L"- Among other names]- Designs, places, and records everything that happens in any sentient thing's life. It ensures that every soul has a chance to "live" or be in as solid a state of existence as every possible thing. Each and every soul gets an untold amount of eternity to figure out the best or core version of who they are (A soul's deepest belief). Those who find their core and pass Death's judgment are given back to Life so they can coordinate with Reality to create the perfect paradise for that Soul. Death and Big G, however, can revoke a soul's right to paradise if their core representation has been cheated in any way... which is often the case, and have them sent back to the cycle.
DEATH ["D"- Among other names]- Categorizes all the information that Life collects and generates a grade for that soul's death, depicted as a pass, repeat, or fail. Death copies the soul an infinite number of times, removing, reordering, or outright fabricating lives and lifetimes that each copy will use as a basis for their next life. The new souls are sent out to live various lives, reflecting each other near infinitely as the original is sent back to complete another lifetime as something or someone else. The souls are then compared and contrasted, throughout every conceivable lifetime in hopes that they all reach the same or an overall conclusion about how they behave or who they are as a person. Those who do find their core are sent to Life, those who don't are sent on a never-ending loop. These people who fail after living every conceivable lifetime within their original species, can make an appeal, in which case, Death is tasked with removing the soul, never to have or will exist. Big G and Life can overrule this decision.
REALITY ["Ray"- Among other names]- Forges the (multi) universal realms and physics that are specific to each person living their life or those in paradise and creates everything that every living thing is tested in. Its main goal is to make sure that there is a foundation for all things that have been, are, will be or (?). Its secondary goal is to ensure that Life does not play favorites in terms of species or placement and that Death does not get carried away with cleaning everything. Its third and most important goal Is to make sure Fate does not get personally involved in anything because it usually involves indiscriminate chaos only Fate would understand, which is harder to deal with than any amount of balanced randomness in Reality's opinion. It and Big G decided to limit Fate as Chaos is good, but too much would lead everything to ruin.
FATE [Aims- Fae- Among other names]- Creates chaos and disrupts the natural order of everything out of boredom, or by some greater design only they know or even understand. Cannot do anything or exert any power because the other Gods run everything with depressing efficiency. There is no particular task this being has decided to take up as its own since so, they self-titled themselves as the God of Fun, Games, and Fate above all else since they had a knack for overturning eternal truths and universal laws through proxy when chance presented itself. The terms, "Deities", "Gods", or even "God", are byproducts of Fate's influence, along with the fate changing immortals of independent cultivation, and inconceivable species of higher orders of existence (Like the ones from Lovecraft's extended universe).
For now, Fate assists Life and Death by creating fun little gimmicks like, Systems or customized universal settings that go against what Reality has in mind with physics, universal constants, and such.