I'm not sure if you're being sincere or not, but I'll take the bait.
I have no qualms with admitting that this largely describes me, although I remain very much mentally and physically active where these people in Japan seem to have lost interest in doing anything at all. I write music; I write prose and am starting to work on essay-like articles on things I find interesting; I go for walks; I clean the house; I bake bread regularly; I play a quick game of chess every day; I read a lot, both fiction and non-fiction; watch films, lectures, documentaries etc. I am fortunate to have managed to re-enter the world of game soundtrack composition under a pseudonym, it provides a small yet survivable income. I had quit for a couple of years after becoming frustrated with the idea of writing to spec, but it's a necessary concession since I am no longer willing to work in an office. I see friends in person probably a few times a month, I've never been a big socialiser, although I am able to act up to it on occasion.
Being saddled with a relapsing-remitting form of depression, I do have prolonged episodes several times a year in which I more closely fit the definition of hikikomori given in the article, but generally I am not that bad. I was in therapy and on medication for the first half of 2011, but I decided to go cold turkey on both because they were making things more difficult for me. At this point I am, granted a clear mind, able to analyse and attempt to deal with my issues on my own. I suppose my eventual goal is to conquer my persistent issues and to "own" my lifestyle, I have serious doubts that I can do so during episodes, but when sober (i.e.: not overcome by depression) it seems both possible and desirable to reach that state.