#kaleidescope

I'm going to talk about it like it's a mha au. The homunculi would still be well homunculi, just a creation of All For One's attempts to create a new and truly immortal body for himself. Pride was a undesirable result that initially sought to usurp him, this could have been about the time that AFO gave Shigaraki his quirk so about twenty years before the cannon start. AFO lets him go expecting him to come back or die in a few days, due to his core (Philosopher's Stone) needing to recharge to keep his body stable or just needing energy to stabilize. But Pride manages to discover that devouring people allows him to turn them into energy for his core and prevent his body from disableizeing and returning him to how he was before (A "stillborn" child, don't ask).

So flash forwards twenty years and Pride is having moments when he blacks out and wakes in a random orphanages. So in his infinite wisdom Pride has a piece of himself pretend to be a shadow and he finds out that his body has a ego of it's own that has slowly been astabithing dominance over him. AKA Selim, who is the polar opposite of Pride and his ego had been randomly taking control of their body. Pride, being, well Pride, doesn't want this to happen so he's been trying to take the body back for himself. Separation doesn't work due to them both being the same person on a spiritual level, and it is extremely uncomfortable and potentially dangerous to be separate for long periods of time. So eventually Pride has to make some form of agreement with Selim for shared use of the body. (They call each other Humility and Arrogance)

Eventually it gets back to AFO that Pride is still alive and has developed healing powers and light manipulation, well Salim has and he found his way into U.A somehow, maybe Nezu figures there's something up with this nine year old that isn't quite normal. So AFO makes more Homunculus like Pride, to hunt him down (Pride is the perfect vessel in his eyes, or at least able to return him to normal) and a couple of encounters later Pride and Selim find out that as long as their core remains in one piece the can revive with minimal effort. Eventually one of the other Homunculus begin to gain a separate self (Greed and Ling) and defects form the L.O.V this continues until all of them have a opposing self. It takes a while to discover that the "other selves" are the people who the bodies were before death and Selim took so long to manifest because he was stillborn. Some accept their others, some ignore them, but Wrath out right dominates his due to his passive nature.