You only can enlighten my friend on one of the most obscure questions of Diabolism." "Which one ?" "That of incubacy and succubacy." Gevingey did not answer at once.

"That is a much graver question than Spiritism," he said at last, "and grave in a different way.

But monsieur already knows something about it ?" "Only that opinions differ.

Del Rio and Bodin, for instance, consider the incubi as masculine demons which couple with women and the succubi as demons who consummate the carnal act with men.
"According to their theories the incubi take the semen lost by men in dream and make use of it.

So that two questions arise: first, can a child be born of such a union?
The possibility of this kind of procreation has been upheld by the Church doctors, who affirm, even, that children of such commerce are heavier than others and can drain three nurses without taking on flesh.