I'm giving this a very tepid recommend. I really liked the overall premise of Etienne's plight and some of the books he enters. Each of those books takes about an hour to complete and I would have liked to see them fleshed out more. They were compelling enough that I think some of them could be the premise of entire games themselves. For that, I recommend the game.

Negatively, I didn't get much enjoyment from actually playing the game. I understand that there needs to be some level of interactivity if you're not making a visual novel, but Bookwalker is just a step or two above that. There are turn-based battles that are pretty pointless. There is nothing complicated or puzzling about finding items and putting them in the right place in order to progress. You are given choices, but outside of a few changes to dialogue, you are essentially on rails through the game.

It depends on what kind of game you are looking for. If you care about gameplay and challenge, you should look elsewhere. If you are interested in the visuals and want unique plot(s), you might enjoy Bookwalker. However, everything else about this game is pretty weak and even interesting ideas might not be enough to get you through the dull parts.