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NHK stands for Nihon Housou Kyoukai, or Japanese Broadcasting Corporation, which includes a few different TV channels in Japan, I guess. However, the main character of this manga, Tatsuhiro Satou, comes to believe it is actually Nihon Hikikomori Kyoukai, which is a secret evil organization with the goal of turning its viewers into otaku, who eventually become hikikomori. It should be noted that this theory was presented to Satou by his appliances, which suddenly started talking to him.

...I imagine if you're bothering to read a review of a manga, you at least probably already know what an otaku is. You may be less likely to know what a hikikomori is. But for an explanation of either word, please check my jisho, then come back here.

Anyway. Satou is a 22-year-old hikikomori. I'm a bit confused on the time frame here... at the beginning of volume 1, he says it's the second Spring since he dropped out of college, and his parents just stopped sending him money (since he has no job). He then says he's locked himself up in his house for four years, though that makes no sense to me if he dropped out of school just two years ago. But whatever, it's not important, I suppose. The important thing is, it's been at least a couple years since he left his house. He'd like to stop being a hikikomori, he starts thinking of leaving the apartment and looking for a job. And then, a missionary lady named Kazuko, and her 18-year-old niece, Misaki Nakahara, show up at Satou's door with a pamphlet about hikikomori, which kind of makes him flip out and act crazy. When they leave, he starts taking some mail-order drugs, which is when the appliances start talking to him.

Well, to be honest, this at least explains the title of the series, but it's not really about the N.H.K., as far as I can see. I don't think Satou really believed what the appliances told him, because soon after that, he decided to finally leave his apartment and look for a job. Trouble is, the first place he stopped into, he saw Misaki again. And... well, his mental state being what it is, he's really not good at social interaction. Especially with a cute girl like her. His mind tends to start going places that make him feel ashamed, so of course he gets away from her as quickly as possible. He goes back home, and then confronts a neighbor who moved in recently, who is constantly playing music from anime, which bugs him. And it turns out his new neighbor is Kaoru Yamazaki, who was an underclassman of Satou's in high school, and is currently a college student. Yamazaki is a major otaku, with a grudge against women, because they want nothing to do with him. So he escapes into fantasies about anime girls and the like. And he tries to convince Satou that Misaki is no good.

But then, Misaki shows up again, and invites Satou into her project, to help him stop being a hikikomori. Of course, he tries to convincer her that he's not a hikikomori, and this leads to him lying about being a videogame designer. Then he goes to Yamazaki, asking for his help in this bit of deceit, and Yamazaki decides they should make an erotic game, which Satou will write the story for. Satou doesn't really want to do this, but gets involved anyway, and the research causes him to develop a Lolita complex, which only makes him more ashamed of himself and more uncomfortable around Misaki. Though loli-con makes Satou an even more desirable participant to her for her project....

Later, Satou meets up with Hitomi Kashiwa, who was an upperclassman in high school. Now, she has lots of stress from her job and whatnot, and so she takes a lot of drugs, legal or otherwise. Anyway, they used to be friends and apparently he had feelings for her. Another old classmate he eventually runs into is Megumi Kobayashi, who was class president, and who now is involved in a pyramid scheme....

Well, I feel like I've basically said enough for now, I just wanted to set up the basic plot and mention the major characters. Actually the main ones so far seem to be Satou, Misaki, and Yamazaki. All kinds of strange, funny situations develop that I don't want to spoil, or anything. Basically Satou seems to be pulled in different directions by his friends, if you can really call them that; Misaki trying to cure him, and Yamazaki making him even more of a hikikomori. The theme of the N.H.K. conspiracy resurfaces now and then, but so far I haven't seen anything major done with it at all. But I'm just through volume 3, as I write this, and there are 8 volumes in total. So I've still got a ways to go. Other than that, I should mention that each volume includes a few four-panel comics, between chapters. And at the end of each volume, we get to see some notes, apparently written by Satou, about his progress on the story for the ero-game. Which is both interesting and amusing. Plus a glossary with explanations of some Japanese terms and cultural references, which appear throughout the manga.

Most likely I'll have more to say about the plot after reading more volumes, but as I said, I don't want to spoil too much. It's really fun to see what happens, just how crazy and surprising it can all be. Of course, there's also more to learn about the characters, like just why Misaki feels compelled to try to help Satou. But what really draws me to the story is that I identify so much with Satou. Okay, my appliances have never talked to me, and while I may enjoy some wacky conspiracy theories of my own, I don't really put any stock in them. But I think... seeing the inner workings of Satou's mind, some of the fantasies he has, his social anxiety, feelings of shame, and all that... it really reminds me of myself, to an extent. My fantasies may not be quite as vivid or disturbing as some of Satou's, but otherwise... I definitely empathize with him, and feel like if people read this manga and got to know Satou, it might help them understand me a bit better...

Well now, I hope I'm not forgetting anything I meant to say, but I should be updating this again sometime, as I've said. And aside from the identification, it's also really amusing and interesting, and of course, Misaki-chan is just too cute...!