Why? Because Episode 13 occurs chronologically before all the other episodes, and is a whole lot more enlightening if viewed first, and, I'm sure, will make your viewing experience much more enjoyable. It's a waste of time to see the "first" episode at the very end, because, by that point, you can pretty much fill in all the blanks yourself.
As for the show on the whole, it elicited a lukewarm response from me. At first, it deceivingly markets itself as a comedy, when it truly follows more of the drama/slice-of-life genre, although the drama is mild and far-between.
The only thing driving this show is the characters, comprised of a diverse cast of different personalities. Hyakko's characters are certainly the only thing that saves it from its less-than-lackluster plot.
On the whole, Hyakko is decent. It wasn't for me, but if you're into this kind of genre (and the characters especially), it's certainly worth a run-through.
