Board Thread:Questions and Answers/@comment-84.195.250.138-20140909190917/@comment-4755115-20160321015300

No, it couldn't be extended into a twenty-six episodes series because they were too close to where the manga was at that point in time and there wasn't a good ending point. And the series would have to resort to filler to reach the number that you want and you know that filler is rarely any good for an anime adaptation. Of course, with the plot development that's occurred in the last three years, they could  possibly extend the series into a twenty-four episode anime (up to the point where Akimu becomes the new Demon King after absorbing Richarz and Grimm's power) with additional content to begin a second season.