57465934_p* or _m or _master or _big or (varies depending on when the picture was saved and whether it is a thumbnail)
-> pixiv picture
-> illustration id is 57465934
-> http://www.pixiv.net/member_illust.php?mode=medium&illust_id=57465934
-> http://www.pixiv.net/member.php?id=945189

When this doesn't work:
http://www.google.co.jp
http://saucenao.com/search.php?db=999&url=https%3A%2F%2Fwww.gurochan.cx%2Fs%2Fthumb%2F1473700152480.png

Five seconds of searching saves you five minutes of posting.