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The apple doesn't fall far from the succubus family tree.

The Alu-Fiend is a fiendish race introduced in The Lost Caverns of Tsojcanth for Advanced Dungeons & Dragons, as the alu-demon. Specifically, they are the half-fiend daughters of Succubi - which makes them the female counterpart to the cambion race and a likely direct progenitor for a tiefling. Second edition wasn't allowed to use the D word, so the Planescape setting (Monstrous Compendium Outer Planes Appendix and the Planescape Monstrous Compendium Appendix) restored them as alu-fiends and that name has stuck.

In practice, the alu-fiend is basically a wimpier version of its succubus progenitor, with similar spell-like abilities to charm people, read thoughts and teleport away from danger. They are characterised by hating themselves extensively, due to feeling like they have no place amongst either humanoids or fiends. Weirdly, though they aren't all evil, they are actually more evil than their cambion cousins; cambions can potentially be Chaotic Good, but alu-fiends can only be Chaotic Neutral or True Neutral in place of their traditional Chaotic Evil alignment.

Because they really didn't have a niche for themselves beyond "watered down succubus", they vanished with the creation of the Half-Fiend template in 3rd edition. Fifth edition shoveled yet more dirt on the grave by making cambion a gender-neutral term.

The closest thing to a nod to their existence was the creation of a web enhancement that details a Half-Succubus "variant" of the standard half-fiend template, which can be found here:

They are named after Alû, a demon/spirit from Mesopotamian mythology.