Sadly, I can’t find the light novels, and the manga doesn’t go so far yet. 🙁
The manga (and probably the light novel) are very close to the anime, I was at times a bit bored, because I already seen those scenes in the anime.
So far I haven’t met any characters that I didn’t like, they all have their traits and they are all fun. Maou, our demon overlord who now works at a McDonalds. He and his servant live in a run-down apartment. And then we aren’t even talking about his enemies who drop from the heavens to hunt him down.
There was only one thing I didn’t like, the unnecessary amount of nude in regards of the hero girl. She is the only character who we keep seeing naked (shower/undressing/in flashbacks as the hero).
The manga is comedy, but also has action, fantasy and a bit of romance.
I would recommend this one to everyone who needs a fun manga.