Even before the Great Passive Aggression, Incest was already widespread and openly practiced within Dark Elf society. During those dark times, sex was yet another means of oppression of the strong against the weak and submitting to the whims of a more powerful partner, within or without the family, was the norm.
Things have now changed and the new creed of the Goddess demands all displays of affection be consensual and to the benefit of all parties involved. According to Lolathian doctrine, sexual interactions with a family member are seen as the breaking of a false taboo that was never meant to be and must be overcome at the earliest age. It is tradition that every young dark elf is introduced to the joys of sex by the closest of kin, be they sisters or cousins. Once a dark elf maiden has reached her one hundredth birthday, she will be initiated to sex by her mother.
Still, not every dark elf embraces this custom with the same amount of enthusiasm. A few dark elves, especially those belonging to the youngest generation, avoid even the very idea of sexual interaction with their parents, siblings, or children. None would dare challenge the orthodoxy of the creed out loud and avoiding the advances of a close relative is always a complicated matter.
This is of great concern for the matrons sitting in the Ruling Council, for the weakening of the lustful zeal amongst the youngest may be an ill omen or, worse yet, an open defiance to the perverted creed of the Goddess.