https://www.pixiv.net/artworks/118941824

Base +29

I think you downloaded the images incorrectly. I downloaded it myself, the entire 23 pages is suppose to be 129mb. You must click on the images first to enlarge it, then right click "Open image in new tab", to get the actual resolution. Or you could use a Pixiv downloader.

Base +8, kirasky123 +6, Pootis Spencer +6, Akdav +8

Yeah these are the preview samples, not the full images. You can tell from the "master1200" in the filename. It's only a third of the full resolution.

Base +16

https://www.melonbooks.co.jp/detail/detail.php?product_id=2062646

Base +65