That's Mado-sensei for ya. She has always had an incredible art style.
That being said, I miss when she used to draw tomboys. That one doujinshi about a dude giving a massage to a tomboy gyaru is still kino.
That's a cool arachne design on page 14. While I can definitely see it as a "spider woman", I can also squint a bit and suddenly it has the look that it was just a spider with some weird and highly detailed camouflage and lure. Having the "woman" bent over backwards with her head hanging down allowed the "hair" to be formed from the spider's pedipalps. And the spider's eyes on its normal body get to to look like they're covering the woman's chest, while seeming perfectly natural for eyes to be in that spot in the first place.
The only part that doesn't seem quite right when I squint is the presence of a neck on that head.