Board Thread:Lore Discussion/@comment-129.21.143.199-20130911211744/@comment-84.26.230.30-20140523185726

Most likely karliah, as the last possible septim heir (related to baranziah) so yeah, a thief becoming emporer. basically the thalmor destroy the empire ressurect alduin, enslave him and rune has to stop them from destroying the world. after that he becomes the emporer of the rune dynasty.