According to https://www.mangaupdates.com/series.html?id=137510, there are 8 chapters total, with not all completely scanlated.

The author's twitter is @ononon, and his Pixiv ID is 1100886, and his email is on his website, in case anyone who knows moon wants to see if he's said anything about it.

I did (just, within the last 2 minutes) find 6 chapters, apparently all translated, at http://www.mangago.me/read-manga/disabled_girl/, but that means it must be missing two (if 8 is the correct total).

Apologies if this is considered spamming, but I remembered Bikko from ages ago, and became extremely curious to see what became of it.