The Black River Rises
The Black River Rises is a story written by Domashita Romero and illustrated by pseudonymeter and quaedam. It ran in Issue 34 at http://s2b2.livejournal.com/202617.html, and is mirrored at http://www.shousetsubangbang.com/mirror/the-black-river-rises/.
From the author: "The River is cold and black and deep, and the men there must guard it for all of their lives. I’ll be the first to tell you this got its start as Game of Thrones pastiche, but it went pretty different places. With sexy results! And also WAY MORE DOGGIES!"
From isis.dreamwidth.org: "A nobleman's last and most worthless son joins the varied men who are guarding their land from the horrors on the other side of the river, with sex and worldbuilding."