I posted about this in the "News" section, but I'm going to repost it here just in case I wasn't supposed to post there (gomen).
As of April 5, 2016, there's a new petition to bring Kyo Kara Maoh! back for a fourth (4th) season and a remake of the animated series. The goal is to gather 2,000+ signatures as well as comments before sharing the petition with NHK, Geneon and everyone else involved with the series. Click the link, or copy and paste the link into your browsers address bar, to view the petition, sign it, and to leave comments.