Onii-chan no koto more or less, deals with three girls who like the same guy for the wrong reasons. The plot in itself, isn't anything special, being more or less, your standard ecchi comedy. The humor usually didn't cut it for me, though it had a few chuckle moments. The one thing that separates Onii-chan no koto from other ecchi comedies would have to be the main girls themselves.
Nao, the main character, is a step sister who has though she was a sister for the length of her life. A car crash left her orphaned (and conveniently, gave her amnesia so she forgot everything that happened before) and she becomes adopted her dead father's friend, who has a son who's about a year older than Nao. For whatever reason, Nao decided to become a closet pervert (though not exactly, since her secret is well known by her close friends), who “wants to be in a forbidden relationship with Onii-chan for the thrill of being in a forbidden relationship.” Once she discovers she's not a biological sister (which manages to happen in the first episode), the back story is never mentioned again, except by many girls who quickly reference that she cannot be that close with her brother. As much of a spoiler as this sounds, I more or less, just described the first episode, so if you're reading this review before watching the show, you're going to see it immediately anyways. Basically, the story line won't be dealing with incest. It's just another pervert girl with aho-ge. Admittedly, I find it cute when she pretends to be innocent to entice her brother, then does her “3...2....1....fan service time over. =S HENTAI!!!!” bit.
The Onii-chan in question is Shuusuke. Hiding porn in quite literally every inconspicuous centimeter of his room, he's probably the most blatant pervert ever to exist in animation/manga. He's rather dense about the fact that three girls are out to get his lips/in his pants/his nipples, he's a weakling who is easily pressured into doing something, and he's somewhat respectful on top of that too, so he's a male stereotype. For the most part, I found his performance throughout the series rather bland, and could only pick out about 3 scenes across the 12 episodes which I found “not boring” to watch him in. To sum him up, he's the plot device that every girl (who part of the main cast) wants, and every guy (aka fellow pervert) wants to hang with.
Rivaling Nao for the race to Shuusuke's heart is Iroha, a childhood friend overloaded with stalker technology who took a promise way too far, and Mayuka, a model student/class representative who secretly goes out at night to buy and read Yaoi books, and has a strong nipple fetish.
The rest of the supporting class feature Shuusuke's group of friends who enjoy porn as much as he does, and Shuusuke/Nao's parents. The parents don't play much of a role, merely existing to explain Nao's origins, while Shuusuke's group of friends effectively try to get him to actively share and discuss porn, which he, being the biggest pervert he is, agrees to. I personally didn't care for their antics, but they get into odd situations involving their hobby, which made for some okay drama and development.
Each of the three girls get their moments to star but for the majority of the series, it's really just Nao and Iroha fighting with each other, while Mayuka makes a(n) (innocent) move. It was sorta funny the first time, but even after doing it in about four different situations, it gets pretty repetitive. The saving grace of whatever is left in the plot is the relationship between Iroha and Nao, which I find rather intriguing. Rather than just duke it out when along with Shuusuke every time they appear on screen, their rivalry goes as far to try and prevent any other girl from making a move on their Onii-chan/Shuu-chan. It's pretty fun to watch their inner thoughts seem to have a conversation with each other, as they allow their actions to convey their words. The understanding between them, to the point of considering each other friends, is pretty cute, and has been the main reason I watched the series through to the end. Mayuka's solo time was also quite cute, though I wish all of the Yaoi-esque moments could've been toned down a bit. There's also an additional anime-exclusive, though its only purpose seems to be to create a few yuri moments (probably to subvert all of the yaoi I had to endure, blech).
the character models, though unique, and pretty weird to look at. Bony body structures, baggy eyes, and an overall beat up look. At times, it makes me feel like I watching rape victims assimilating to a new lifestyle. The characters are so malnourished that several potential fan service shots are blocked out by fuzzy penguins and cats, just so people don't have to stare at their horror. Okay, that's not the real reason for the cutesy censors, but it's not hard to tell that they were likely unappealing. Even the opening had a full-on frontal panty shot, so the censors just felt unnecessary. In effect, the two aspects that make an ecchi series (fan service and hot/cute characters) are never completely there. Animation is sub standard, which wasn't too surprising. Character designs are generic, though they do their job.
The sound is fairly standard. Background music consists of a soundtrack which almost feels like a parody on romance dramas. Anything else easily fades into the background. Sound effects are quirky (I swear I heard the scooby doo running one once) though they get the job done. The voices for the cast were overall good. Eri Kitamura does a great job voicing the adorable Nao, Marina Inoue makes Iroha sound more mature than she appears, and Kazusa Aranami (a lesser known seiyuu) does a pretty nice job as Mayuka. The opening and ending songs are standard J-Pop, though the ending song is pretty damn catchy.
Overall, “Onii-chan no koto nanka zenzen suki janaiin dakara ne!” (try saying that 10 times fast =_=) is your typical ecchi comedy. The main girls are the show case, and despite their rare perks, they will act cliched at times and repeat similar situations just on a different background. If you don't mind the character designs (and the yaoi about mid way in), this anime can provide a few chuckles, but there are better ecchi comedies out there. If you came in expecting some actual incest, then you're kinda sick/you'll be disappointed.
