I don't think he has a Pixiv account anymore. The previous one was locked, so now he uploads to these sites: http://nijie.info/members.php?id=1034 http://seiga.nicovideo.jp/user/illust/996060?target=illust_all Log in through Twitter or whatever for these.
There's also this tiny gallery but not worth writing home about. http://twicsy.com/i/5Bpd8
And if you're really interested, check his Twitter occasionally for rough sketches. https://twitter.com/gomesu_orz