Hey /ss/,
Pixiv seems less notable than other sites in terms of gathering h-images, but it's a huge goldmine for people who are willing to look. In my quest for /ss/ I've come across a lot of great artists there but I'm sure there are more that I'm not finding. I say let's share what we know. For anyone who can't interpret moonrunes, "おねショタ" is the Japanese equivalent of "straight shota" and will get results.
Kloah13 (known as Kloah on English sites)
http://www.pixiv.net/member_illust.php?id=283027 そーすけ
http://www.pixiv.net/member_illust.php?id=3437369なめジョン (known as zzinzinz on English sites)
http://www.pixiv.net/member_illust.php?id=293363shuz (しゅーじ)
http://www.pixiv.net/member_illust.php?id=59551And a few more of my favorites although their particular fetishes might not be for everyone:
茸 ("Mushroom")
http://www.pixiv.net/member_illust.php?id=1527494and 顎 ("Chin", known as Hatomame on English sites)
http://www.pixiv.net/member_illust.php?id=9146both love their monster-dicked shotas
and rrsmb has a thing for the shota tying up and BDSM'ing his onee-chans
http://www.pixiv.net/member_illust.php?id=1023017