No, I mean novels, as in actual books. I don't own any, but there's around 10 novels or so, and it still hasn't ended. The anime takes parts from the novels and had a made-up ending compressed into 24 eps, thus the plotholes and rushed ending someone pointed out. I think the manga came after the anime, but I'm not too sure. The novels also have a few picture inserts drawn by Mogudan, who has far greater art than the artist that does the SP manga Here's a few of the picture insert scans I've found from the novels: