Sorry for bumping an older post, but when exactly did Harima's career as a manga artist end? I don't think he's stopped working there, it just hasn't been touched on in a while as other stories have gone to the focus. Though I may have missed something
If you look at KJ's manga career, he won Shounen Magazine's Rookie award, which was what gave him the opportunity to serialize SR in that same magazine, in 2001. Harima's manga career initially follows the same lines, but then diverges completely - while Harima wins the amateur manga award and gets his big chance, he messes it up and his manga career comes to an end.