- Broken Base: The Reveal that Kyousuke isn't Maou certainly split the fanbase in half. Some praise it as a surprising plot twist and enjoy the action-packed final chapter it leads up to. Others absolutely despise it, seeing it as a blatant Writer Cop Out that creates many plot holes and contrivances, makes Kyousuke less interesting, takes away most of his moral ambiguity, and presents us with far more clear-cut and cliche conflict.
- The routes other than Haru's. Some enjoy them, while others see them as pointless, boring additions that don't contribute to the story, abandon its tone and genre, and create numerous contradictions.
- Ensemble Dark Horse: A lot of people are disappointed to find that Yuki isn't a romanceable character.
- Moral Event Horizon: When you learn that Maou used a terrorist attack in Russia as a convenient way of killing Kaoru Mishima, Haru's mother, simply because she is the wife of the person who ruined his father's life, you will despise him, if you have not already done so when he kidnaps Tsubaki's kid brother, Hiroaki, then proceeds to corrupt the poor girl.
- Suspiciously Similar Song: Practically all of the background music used is a variant of famous classical music pieces, ranging from Bach to Wagner to Grieg.
- Unfortunate Character Design: Eiichi's costume when he and Kyousuke are playing "God" looks a lot like a KKK robe.
- Villain Decay: Mephistopheles/Saijou in chapter three initially comes off as a cold but honorable right-wing extremist, later he is revealed to be more of a sociopath who is easily manipulated and controlled.
YMMV / G-Senjou no Maou