Using HTML as Corion suggested does not mean you need to build a 'CGI' app, it is only a means to display your characters. The app need not live anywhere but on your computer, You'd just display the HTML files your app produces locally. It's a good idea!
It works for displaying, yes, but I would prefer a more convenient interface where I could type my response into the same window as the character is displayed in (of course, for all I know, this is possible with HTML).
Please correct me if I'm wrong.