Cambion
In mythology and literature, a cambion /ˈkæmbiən/ is the offspring of an "incubus or succubus" and a human.
A cambion is most often depicted as the offspring of an incubus or succubus and a human.
The earliest evidenced appearance of the word in this sense is in the 1818 French-Language Dictionnaire Infernal. The 1825 edition of that book has the following entry:
CAMBION, -- Enfans des Demons. Delancre et Bodin pensent que les demons incubes peuvent s'unir aux demones succubes, et qu'il nait de leur commerce des enfans hideux qu'on nomme cambions....
Translation: CAMBION, -- Child of Demons. Delancre and Bodin think that incubus demons could unite with succubus demons, and that born of their exchange were hideous children which are called cambions.....
The word cambion previously appeared on an early 1st century AD inscription in Gaul (Roman France). Linguist Benjamin W. Forston IV opines that:
...cambion is from the Celtic root -kamb 'crooked', also referring to back and forth motion and exchange. It is ultimately the source for English change via late Latin cambiare, a borrowing from Celtic.
Given the above, it's probable that the word, as de Plancy defined it in 1818, is a cognate for changeling.
The Malleus Maleficarum does not use the word but states that demons, including the incubus and the succubus, are incapable of reproduction:
Moreover, to beget a child is the act of a living body, but devils cannot bestow life upon the bodies they assume; because life formally proceeds only from the soul, and the act of generation is the act of the physical organs which have bodily life. Therefore bodies which are assumed in this way cannot either beget or bear.
Because of this inability to create or nurture life, the method of the creation of a cambion is necessarily protracted. A succubus will have sex with a human male and so acquire a sample of his sperm. This she will then pass on to an incubus. The incubus will, in his turn, transfer the sperm to a human female and thus impregnate her.
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