A very fat MC is unusual and may as well be interesting to read. Add into the equation the betrayal of the humans and him being assisted by demons, then it is worth a read even if just as a change of pace having nothing else to read. It's just that the progress is a bit fast-paced like most fantasy genres with swords and magic. You would even see your typical tropes of antagonists who are too greedy or even a tsundere elf. Basically, this series is like a walking trope. It's not that bad, but not that good either. At least character types and personalitiesvary in here, which is great.

Again, it's a good read if you're looking for another series to start on or go back to.