Succubus and incubus

Succubi and incubi are shapeshifting fiends who delight in the corruption of mortals through temptation. They are the same race; the female is a succubus and the male is an incubus.

Appearance
Succubi and incubi are shapeshifters who can polymorph into Small or Medium humanoids. In their true form, succubi appear like beautiful humanoids with a fiendish twist, almost tiefling-like, with clawed hands, leathery wings, and sharpened teeth.

Abilities
The following is all drawn from the Monster Manual, but it is consistent with what a succubus and incubus are seen doing in and.

The method succubi and incubi typically use to corrupt mortal souls begins with approaching them in their sleep (passing through walls in ethereal form to get to the sleeping chambers) and filling their dreams with debauchery. The succubus/incubus proceeds to appear in the flesh in the same form that was projected into the dreams, indulges the target's desires, and seduces the mortal into evil thoughts, words, and deeds of their own free will. This way, when the succubus/incubus kills the mortal, the target's soul descends to the Lower Planes. Therefore, although the succubus and incubus have a powerful magical charm, they only use it as a last resort, typically to defend themselves.


 * Resistances: Cold, fire, lightning, poison, and bludgeoning/piercing/slashing from nonmagical attacks
 * Etherealness: Switches between the Material Plane and the Ethereal Plane as an action.
 * Shapechanger: Magically polymorphs into a small or medium humanoid of the same sex, or back into their true form, keeping all equipment and statistics (except that without wings they cannot fly). Reverts to their true form upon dying.
 * Charm: A humanoid the succubus/incubus can see within 30 feet must succeed on a Wisdom saving throw or be charmed for 1 day, during which the target follows the fiend's verbal or telepathic commands. The charmed creature can repeat the saving throw whenever it is harmed or given a suicidal command. If the succubus/incubus charms another creature, their charm on any other creature breaks. Once the creature makes a save or the effect ends, the creature is immune to that fiend's charm for 24 hours.
 * Telepathic Bond: A succubus/incubus can communicate at any distance and even between planes with any creature they have charmed.
 * Draining Kiss: Usually delivered as a coup de grâce, the succubus/incubus kisses a charmed or otherwise willing creature, which takes psychic damage and suffers an equivalent reduction in maximum hit points until the creature completes a long rest. If this reduces the creature's maximum hit points to zero, the creature dies.

A succubus can become an incubus, and vice versa, but they tend to prefer one form over the other.

Society
Succubi and incubi can have offspring with each other. Sometimes a succubus or incubus will procreate with a humanoid, and the result is a cambion.

Succubi and incubi sometimes operate in the same spaces as devils without being a part of that hierarchy, and the City of Dis in the Nine Hells is a popular place for them. Likewise, they sometimes end up in the service of demons (see below, in History).

Campaign 1: Vox Machina
When Vox Machina arrived in Emon for the first time, Syldor Vessar hired them to look for Sir Gregory Fince; when they investigated Fince's home, they found his tortured corpse in the basement, and they discovered and defeated a succubus and some demons.

Campaign 2: The Mighty Nein
In The Bright Queen's Favor, the Mighty Nein investigated a demonic incursion in Asarius and interrupted a succubus and incubus attempting to corrupt a sleeping bugbear named Umadon. The party gave chase, following the fiends to an underground chamber where an Abyssal anchor had torn a rift through which demons could pass. The demons were attempting to build a stable portal from the Abyss beneath the city. The succubus used her charm to turn Caleb Widogast against the party, to terrible effect, and the incubus was able to charm Fjord.

The background for the adventure Merry Spouses of Deastok in the Explorer's Guide to Wildemount notes that incubi and succubi have married into the powerful Truscan family of the Dwendalian Empire over the previous decade.