Zathura will by default keep a history and your position in each document, which I personally don't like (I want it to start from the beginning each time) but you can change this with 'set database "null"' in the config file. I tried zathura for pdfs a while ago but went back to evince due to the nice feature of showing all search results in a sidebar when you search. Unfortunately evince doesn't support epub. My zathurarc so far is:

  set database "null"
  set adjust-open "width"
  set scroll-wrap false
  set font "monospace light 24"
  set statusbar-home-tilde true
  set window-title-home-tilde true
  set window-title-page true
  set guioptions "v"
  map [fullscreen] <PageDown> scroll full-down
  map [fullscreen] <PageUp> scroll full-up
  map [normal] <PageDown> scroll full-down
  map [normal] <PageUp> scroll full-up

The font option just seems to cover the interface font (which is tiny if you don't set it) and guioptions "v" means no default status bar but always a vertical scroll bar. Page up and down use viewable pages instead of the default document page.

I was also just looking for an epub reader due to this Humble book bundle on game design that mostly only has epub:

https://www.humblebundle.com/books/all-about-gaming-mit-pres...