Thanks for the yuri book! I've used ECT (https://github.com/fhanau/Efficient-Compression-Tool) to losslessly optimize the JPG and PNG files to reduce the book's size by 4.8% with settings "-9 --reuse" (for the png files.) It's not much, but you might want to think about optimizing your files this way. Here is the download for the book:
https://files.catbox.moe/as6v1d.zip

And the results of the page optimizations. ECT uses modified versions of zopflipng and jpegtran to compress files.
https://files.catbox.moe/mtjbfi.txt

Base +12

Thanks for the recommendation, will try and use it the next time!

Base +1

pg 5, "the current is umi-chan is better" -> "the current umi-chan is better"

pg 6, "if its umi-chan," -> "if it is umi-chan"

pg 15, "that maybe true," -> "that may be true,"

pg 15, "what I said maybe true..." -> "what I said may be true..."

Base +6

For future projects: PLEASE use the original sized images for editing and not e-hentai's downscaled 1280px horizontal res images. They are for viewing and not for editing.

You can download the original resolution images via one of the following methods:
1. Torrent Download (if available; WARNING torrents not always contain the latest or the full res version of a gallery. Downscaled torrents normally have 1280x in their names)
2. Archive Download (click on "Archive Download" and "Download Original Archive"; e-hentai account and some GP or Credits required)

In case you don't want to download an entire gallery:
3. The "Download Original" link at the bottom of each individual image (if there is noch such link the image on your screen and the original are identical) [e-hentai account and GP or Credits required now]

Additional Q&A:
Q: Does that mean I have to upload different sized versions of my images?
A: No. You just have to upload your original sized images. All other resolutions that e-hentai displays depending on the users settings will be created by e-hentai.

And by the way there is a much more efficient and easier way to reduce filesize.
Instead of saving your B/W images as Fullcolor RGB with 32-bit colordepth simply save them as grayscale with 8-bit colordepth. To change the image to greyscale click on "Image" -> "Mode" and "Greyscale" in your editing program.
To reduce the filesize even mor level your images so that the black areas are realy completely black and not full of noise.

Base +18, 2nd_ +9, AkiTooru +15