Reading comments

I'm looking for a plugin that makes it easy for me to annotate text with my own thoughts (for example for me to write commentary over passages in the bible). This plugin seems to provide that functionality, but I haven't figured out how to get it to work. When you add a comment, it wraps the selected text in HTML which then shows a comment when you hover over it. Except the hover functionality isn't working on my machine. I'm not sure why.