A sequel that's better than the original in many people's opinions, though I'm not sure I agree. It's the same characters in the same kinds of situations. I couldn't see much difference on an episode-by-episode basis... you could splice Enishi back into the original series and never know which episodes came from which show. It's lost none of its charm, but I have a few niggles.
Firstly continuity has been handwaved. I'm grateful that it's not a reboot or a parallel universe, but I don't just mean details like whether or not Tina's English is rusty. Ai Yori Aoshi
brought its central love story to a satisfying conclusion. Kaoru and Aoi thrashed things out with their parents and then, um, consummated. I'd assumed that everything was then fine and that Kaoru and Aoi could at last tell everyone... but no, two years later, it's still a secret. That irritated me for a while. It's not technically a contradiction, but it is laziness from writers who don't want to leave their established comfort zone.
Secondly, the Aoi-Kaori love story is complete! The show doesn't split them up again or anything as annoying as that, but the last few episodes are driven to Tina Foster of all people for climactic drama. It's surprisingly powerful and arguably a better ending than the original series had, but one still feels that there's something arbitrary about it.
I think Enishi is better-reviewed because it's more streamlined. The awkward storytelling edges have been smoothed away. You won't get whiplash with sudden genre shifts, the first episode instead being a perfect introduction to the show. A boy lives with lots of girls who all secretly love him. You'll groan, but you'll know where you stand. There's also a new theme (Enishi, literally "the bonds that tie people together") which is spelled out in dialogue and is even in the damn title. The show lets you know what to expect, basically. Thus one sees daft reviewer comments like "Tina doesn't grope breasts any more", even though I think she grabs more tits in these thirteen episodes than she did in the previous twenty-four. She flips skirts too.
Enishi is comprised of a twelve-part TV series and a 13th OVA episode. The latter is a fifteen-minute fantasy prequel to the original series in which Kaoru meets a curvaceous Santa Claus with magical powers. It's a surreal change of direction for a completely real-world show, but beyond that I'm unqualified to comment. I'm sure I'd have loved it in the original Japanese. I had to suffer the dub. My ears, my bleeding ears! It's not even just the fact that to me American accents feel wrong... the dub's Santa-Aoi inflicts a ghastly one-note performance that will make you want to torture kittens, while Chika's American actress does the impossible by being more tooth-shatteringly shrill than any Japanese seiyuu I've heard. However it's a nice prequel to the series, if you view the gratuitous appearances of series regulars as foreshadowing.
Anyone who enjoyed Ai Yori Aoshi
should watch Enishi too. Even the fanservice is as good as last time! It's more of the same, a pleasant return for old friends in charming stories. I liked it a lot.