I asked support if it was possible to use Enpass without administrator permissions back in December 2015. The answer was "Sorry, it is not possible to install Enpass without Admin permission."
I then suggested that they make a portable version (LastPass, and Keepass have portable versions), and was told it's been added to their roadmap.
Actually, if you have admin permissions on another computer, and can install Enpass on that computer, then you can simply zip up the "Enpass" folder in "C:\Program Files (x86)", copy it to another computer without admin permissions, unzip it to any folder, and simply run it from there without admin permission. If this works, then surely creating a portable version shouldn't be difficult?