Well here's one.

(image resaved as a PNG because the filesize was actually smaller that way)

Source: http://www.pixiv.net/member_illust.php?mode=medium&illust_id=51470415

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>>7983
The closest one I can find is the following two tags that essentially mean "body modification". You can sometimes find this type of artwork with either tag, but you have to sift through a bunch of other stuff as well.

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=人体改造

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=肉体改造



You could also try these tags which essentually means "strange", abnormal", "deformed", "mutant", etc. Again, you'll have to sift through quite a few things however:

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=異形

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=異形娘

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=異形化

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=状態異常

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=奇形

http://www.pixiv.net/search.php?s_mode=s_tag_full&word=奇形美



Lastly I recommend using the Pixiv++ userscript since it can give you preview thumbnails of all the pages in an image set, which is very useful for such "sifting":

https://openuserjs.org/scripts/TimidScript/%5BTS%5D_Pixiv++