Sleazy Fork is available in English.
Partially fade/remove non-english, HQ thumbnails, mark as read, subs, version grouping etc.
The script hasn't been optimized with mobile in mind. That is something I've been considering so I might do that at some point though.
The number of thumbnails per page will not change regardless of their size, because the site itself only loads a set number of them per page. That's also something I could fix with some AJAX magic. I might make an option to make the pages infinitely loading, i.e. whenever you scroll to the bottom more thumbnails get loaded in automatically, with the side effect smaller thumbnails means more thumbnails loaded.
For now, I made it so that if you set thumbnail/thumbnail-container width values to 0, the script leaves those values of the page untouched, i.e. NHentai default.
UM hello... I was wondering how to make the thumbnails normal size for mobile because in pages it will only show 6 thumbnails per page even when you lower the size in the settings.