Board Thread:Lore Discussion/@comment-72.77.73.35-20140408131341/@comment-174.5.125.210-20141223035724

After you return the skeleton key your contract with Nocturnal is over. Being half dragon you are sort of a half son of akatosh, in the Lore it states 'the sons of akatosh return to his halls' which means that being a half son of akatosh you will return to his realm with all the other dragons you've slain although probably not alduin he probably would have been banished.