Tbf that's mostly exclusively with Kishika and Hahari since one has a hardcore case of Lost-Childhood Syndrome, Abandonment Issues, and pretty much a parentcon, while the other is a Milf and Rich Ojou-sama character with a hardcore case of thirsty dehydration from a lifetime of being a virgin considering the only guy she loved died back in their schooldays and had his daughter through science lol
It just works out that their character pairing is a perfect combination/perfect storm for perfect baby-play, especially since all the other girls run away or smack her when she tries to do anything. The only girls besides Kishika to go along with Hahari's baby-play fetish is Momiji cause she gets to grope them tig ol' bitties and Kurumi but only after she just ate and curbed her Chronic Hangriness, otherwise she's the first to smack her away and make Iku jealous and want to be Hahari at that moment lmfao
