As you might expect with such a storytelling tool, this particular anime is mostly centered on Nanako and her emotions. Thankfully, she is a very appealing character from the start and does evolve throughout the series, which is acknowledged and focused on. Personally, I love seeing characters not only react to events going on around them but also learn from their experience and change through it, and this is one of the show's greatest strengths. Even people you would think are completely stereotypical in the end come out as real people. Misguided, troubled, horrible but still people with believable motivations. All of them are young, most of them are school students, though not all of them are your typical teenage girls exploring life, as you would expect, some are surprisingly and convincingly mature. This allows for a great many of conversations and different relationships, many of which are used to the show's advantage.
There is not much, if any, story here, which I honestly don't mind as long as character development provided feels genuine, which is exactly the case. To be fair, though, things do seem to move forward, which mostly means learning more about character motivations, some of them being built up from the begging till the very end. There are not that many meaningful, by which I mean at the very least named, people here but all of them are given their own arcs and backstories, and at some point I found myself feeling some kind of emotion for each one of them. At no point did I feel ignorant about any of them, even those who are meant to be villains, and pretty generic at that, are able to invoke hatred or at least irritation, they are never boring.
This is mainly thanks to smart writing, which does a great job touching matters which most people can relate to and doing so in quite an intelligent manner, rarely taking the easy way out of the situations presented. Some topics are as typical and timeless as you can get: divorces and other family issues, bullying, suicide, others were surprising to see, like say, rebellion and its effect on both parties. All the dialogues are interesting to listen to, partly because of the superb voice acting, partly because of it using metaphors and allegories in a way that I noticed myself thinking "Yes, that was a good line!" quite a lot of times.
Being a visual media, anime also relays on its art to convey emotions and story elements. "Onii-sama e..." uses a peculiar style I am yet to see in another title. Admittedly, this may be due to me mostly having seen newer ones but still this is pretty far from what people generally t consider anime to be like. It also uses a lot of still-shots but manages to do that just enough for it to pass as an artistic decision rather than an annoyance, mostly used to put additional weight into certain moments. Sometimes the art did feel strange, for example, in the beginning I was unable to tell whether one of the characters was supposed to be male or female; then again, it might be intentional, since she is later often compared to a man.
Music is actually very important for any kind of visual media, since it can dramatically change emotions felt by the audience. I felt it to be more than effective in this show, sometimes being enough to express what the characters feel. Not once did it feel out of place or badly composed, in fact, all of it was recorded using classical musical instruments, none of it electronic, which seems appropriate for the show mostly dealing with timeless experiences of youth.
Overall, I enjoyed every second of it. It was dramatic and intense but also felt quiet when it needed to be. The characters, particularly Nanako, were interesting, fun to watch and felt real. Can't think of anything I thought was bad here.
