The viper room
Dzyd Ed provides the answer to my question regarding Luc's viperish Quasiboros:
The attached is from T.H. White’s Book of Beasts — which I must have read a thousand times in youth.
Also, from The Medieval Bestiary:
Isidore of Seville [7th century CE] (Etymologies, Book 12, 4:10-11): The viper is so called because it gives birth by force (vi-pariat). When the viper is near to giving birth, her young do not wait for the loosening of nature but bite through her sides and burst out, killing their mother. In mating, the male inserts his head into the mouth of the female and spits out his semen; the female, driven mad by lust, bites off his head. Thus both parents die, the male in mating, the female giving birth.