Story:
The premise of Nakaimo is pretty simple: a standard harem with one twist. Unlike something like Oreimo (where the protagonist knows who his sister is and is fine with dating her), the protagonist of this show didn't even know he had a sister (because of some poorly explained head trauma), and is doing everything he can to not end up with her, even though the sister makes it clear that she plans on marrying him. I guess the appeal of this premise is the mystery behind who the sister is, but with one look at the poster, I guessed who it was perfectly. Once that aspect is gone, you get a completely bland, forgettable mess. The pacing was horrible too. The harem has a whopping six girls (one who is added later), and within 12 episodes, they try to give each of them at least 2-3 episodes of focus and "character development". These episodes only exist to make you frustrated about who the real sister is. It's not spoilers to say that each girl is framed as the real sister at least once, and it's just annoying to see that be thrown around so much. I'll get into how that went later, but the pacing ended up a mess because of it, and any attempt at a story is buried behind a ton of worthless fluff. In the first episode, one girl is hit by a truck. There are no consequences or impacts on the story. It's just something that happens.
Art:
The actual animation wasn't that bad, but the art was a pain to look at. The character designs were bad and the quality was the definition of low budget, and that's not even mentioning the ridiculous amount of fanservice found in the worst places. Also, I don't think the animators knew anything about how things look. There was a scene where a girl's dress strap goes untied, which actually can happen, but the animation makes it look like some sort of invisible pervert was untying it behind her back.
Sound:
This is harder to talk about because I don't actually remember any of the OST (that's how boring it was). But, the opening was catchy, and that's probably the only good thing about the show.
Characters:
Take your standard harem cast, boil down any potential interesting character development, and you're left with the starch-bland cast of Nakaimo. The protagonist is so generic that I can't even remember his name, and he's the kind of character who acts however the episode wants him to act with no continuity to his "established" personality, which is the worst type of character. The girls are all standard tropes, but instead of being entertaining or having some sort of twist like characters in other harems, they get no development whatsoever. I mentioned that the show tries to give each of them a few episodes of their own, but those attempts always fell flat on their faces. The characters are boring and generic with no depth at all, and to top it off, they're not even designed well.
Enjoyment:
This anime was a chore to watch. After starting it and then neglecting it for weeks, I had to sit myself down and watch the remaining episodes in one go. Even if I liked harems, I wouldn't like this show. I mean, right before this, I watched Nisekoi (which I actually really enjoyed), so I guess I just got my hopes up.
Bottom line: this anime is a boring, generic, ugly waste of time. There's no reason you should watch it. Even if you're into fanservice harems, you're not going to find any enjoyment here.
