In what world is a 'moth' a better form for a baby to grow up with? Moths and mantis both lay eggs, just like spiders. There is zero reason to 'fundamentally change species to become a MOTH' as a way of having an easier birth. I really like this series, but this was a stupid change that has no way of explaining it which will make any sort of sense.
Literally changing the entire species, complete genetic and material changes in every single way, from a bug with an exoskeleton to a freaking moth... sorry, nope.
Did the author start righting that 'Mothgirl harasses a man' manga before this? Because this feels like a retcon to try to tie to series together in a really sad way.