This is not the full doujin. The full doujin has been (soft) translated over at Danbooru. You can find it here:

https://danbooru.donmai.us/pools/12678

Fun fact: in the series Triangle Heart (of which the whole Nanoha series is a spinoff from), Suzuka's family is made up of vampires. Don't know if Suzuka herself is one, though, but it seems pretty implied by this pic.

As far as I'm concerned, both @SoupTop and @Gagantous are in the wrong, but not for the whole watermarking tl;dr bull as described above. No, it's because neither of them have actually posted a link to the source/release post of this pic (as of this date). This pic isn't even on the artist's pixiv page either. So I have no good reason to believe either of you posted correct translations of this pic, because there IS no source link, despite claiming to have sources for this pic. The imgur link doesn't count; that's not the source anyway.

After hours of scrounging, I found that he has a Twitter account, and the images in question are over five years old. The source and direct twitpics links for them are (2 images):

http://twitpic.com/5bhgo8 (source tweet: https://twitter.com/LuckyNeco/status/80649925049851907
http://twitpic.com/5erezv (source tweet: https://twitter.com/LuckyNeco/status/83182183807860737
The artist's twitter: http://twitter.com/LuckyNeco