With MangaViewer, you can search for any manga directly from its interface and, with just a click, read it. The only requirement is that you have a good Internet connection, but you won't need anything else to enjoy your favorite manga series.
Once you've chosen the manga you want to read, the left side of the interface will show a list of all its volumes, while at the top, you can access options to adjust the pages and so on.
To turn the page, as usual, you'll have to use the left and right cursors, or you can also use the mouse.
MangaViewer is a pretty good application for reading and downloading manga. Despite having an overly simple interface which is also rather ugly, it lets you access hundreds of manga series from all different genres.
Requires Adobe AIR 3.4 (the app will install it automatically)