[kataklasm]

Not the parent but since I get most of my academic literature for university from libgen I usually have .pdfs. Also, I export my university transcripts to .pdf so there's that, too. I read them using a customized Zathura but I really like the concept you put up. I can imagine using this tool for learning for exams, as an example. Have you thought about making a local, offline client? Looks very promising!