Much fun.
~ Animation/Graphics ~
Pretty decent graphics all around. Nothing really mind blowing, but not bad at all. Pretty good all around and animation is very smooth. Good choice of colors and I don't think I would change much from what you have already.
~ Story/Content ~
The great thing about this is that it does follow a simple story line, which slightly keeps me interested in the game, but the humor adds a lot of fun to the game. Simple things that the characters say, simple titles of attacks or spells, name of enemies, etc.. Some good fun stuff in there all around.
The only thing that I think I have to complain about the game itself is that it get's quite repetitive after awhile. The same basic battle system and everything. I do like that you had the choice of different zombies because that helps a little bit, but I wouldn't mind seeing the game play itself change up now and then so it's not so repetitive.
I haven't tested out the person on person mode, but my roommate has and he said it was alright. I'll check it out here soon, but this would be really fun if you could play the story line in two player or even more online or connected by lan. (If it is like this and I haven't noticed sorry, but I still think it would be a great idea)
Some other things that I think would help this game be better would be the ability to upgrade your weapons for a cost of money of course. That or the more you used your weapon the more experience you get. You could think about doing this with the armor and other things also. This isn't necessary, but it would be kind of neat to have.
I personally like not being able to control your partners. It almost gives it a more of a realistic feeling. It might be interesting if you allow people to choose whether they can can control the party or have the party control themselves. Hopefully something like that wouldn't make the game worst as people would have the choice of the style they liked.
Lastly, I think the directions might be a little hard to understand for people who have never played this game before or if people who aren't too great at figuring things out on their own because of the way the partner attacks before you do in the beginning of the game and it can just be confusing all around. Not to me, but I have seen some reviews that were complaining about it.
~ Audio ~
Great sound effects, great background music, and really good voice acting all around in this submission. Those voice actors getting payed? ;P
I really don't think you could improve on the audio any more than you already have done in this submission.
~ Overall ~
A great game, that may get a little repetitive after awhile, but nevertheless a great game for people to play who enjoy leveling up and a good funny story line. Good job. :) Added to my favorites.