Well, maybe he's not the coolest dog *ever*. Check out a film called HACHIKO MONOGATARI for the coolest dog ever. But Damien the cgi dog in Arch Angels was pretty darn trippy. It's the most unusual use of a creepy big black dog since The Omen.
I'm not familiar with the manga upon which this film is based, nor am I familiar with manga-based films in general. But I really enjoyed this flick. What won me over was the creativity of both plot and presentation. Here we have a bizarre story (a bunch of girls at a Japanese convent school attain super powers and do battle with evil Italian submarines while trying to uphold a façade of proper feminine charms à la French aristocracy) which is told through an equally bizarre blend of live action, cgi, illustrations, "bulleting" (that "Matrix" effect of freezing the action and swooshing the camera around different angles) and even a few comic strip special effects like the old Batman TV series. Essentially, this movie is a visual burst of fruit flavours.
I wish I were more familiar with Japanese culture & language, because I could tell that a lot of jokes & humorous situations were lost on me. For example, there's a recurring gag about ramen noodles which confused me. But it didn't take long for me to figure out that it's supposed to be really funny. And before I knew it I was laughing even though I still didn't get the joke.
There are also many subtle situational gags dealing with the prim & proper nature of polite Japanese society. This I equate to the hilarious old Monty Python sketches about British gentility--again, something you may not be familiar with, but you can enjoy the laughs nonetheless.
I've never been disappointed with a Japanese comedy. Check out SWING GIRLS (also starring the lovely & talented Juri Ueno) as well as KAMIKAZE GIRLS (which has a similar theme of Japanese-European identity crisis) and if you like kickass superhero chicks try CUTIE HONEY.