[RPG] What happens to a soul corrupted by a succubus


The lore text on Succubi / Incubi states the following (MM, p. 284; emphasis mine):

A mortal bequeaths its soul to the fiend not by formal pledge or contract. Instead, when a succubus or incubus has corrupted a creature completely — some say by causing the victim to commit the three betrayals of thought, word, and deed — the victim's soul belongs to the fiend. The more virtuous the fiend's prey, the longer the corruption takes, but the more rewarding the downfall. After successfully corrupting a victim, the succubus or incubus kills it, and the tainted soul descends into the Lower Planes.

How should this sentence be interpreted? Is the victim's soul converted into a low-level devil, demon, or another succubus/incubus? Does it get consumed by some fiend like a midnight snack?

And if none of the above are the case, what does happen to it?

I don't think D&D 5e answers this question, so I'm open to other-edition-based answers as well. I'm mainly looking for official lore information based on the Forgotten Realms setting.

Best Answer

The Monster Manual answers this, explaining what you turn into based on where your soul goes. Being killed by a succubus doesn't change your destination, it's the fact that you have an evil soul that drags you down.

When the soul of an evil mortal sinks into the Nine Hells, it takes on the physical form of a wretched lemure. (p67)

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If you wish to become a low level devil or other being, you may need a promotion.

Archdevils and greater devils have the power to promote lemures to lesser devils. Archdevils can promote lesser devils to greater devils, and Asmodeus alone can promote a greater devil to archdevil status. This diabolic promotion invokes a brief, painful transformation, with the devil's memories passing intact from one form to the next.

So, simply be useful, and you may be promoted up from being a gooey, clay mess.

Alternatively, if you go to the abyss, you may be turned into a Mane.

Spawn of Chaos. The Abyss creates demons as extensions of itself, spontaneously forming fiends out of filth and carnage. Some are unique monstrosities, while others represent uniform strains virtually identical to each other. Other demons (such as manes) are created from mortal souls shunned or cursed by the gods, or which are otherwise trapped in the Abyss. (p50)

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Your form here is elevated by how much blood you spill, and whether others promote you.

If instead you go to Hades, you become a larva.

The layers of Hades are called the Three Glooms — places without joy, hope, or passion. A gray land with an ashen sky, Hades is the destination of many souls that are unclaimed by the gods of the Upper Planes or the fiendish rulers of the Lower Planes. These souls become larvae and spend eternity in this place that lacks a sun, a moon, stars, or seasons. Leaching away color and emotion, this gloom is more than most visitors can stand.(p63, DMG)

While in Acheron, you fight endlessly.

Acheron has four layers, each made of enormous iron cubes floating in an airy void. Sometimes the cubes collide. Echoes of past collisions linger throughout the plane, mingling with the sounds of armies colliding. That's the nature of Acheron: strife and war, as the spirits of fallen soldiers join in endless battle against orcs devoted to Gruumsh, goblinoids loyal to Maglubiyet, and legions assembled by other warmongering gods. (p66 DMG)