YMMV / A Demon Lord's Hero

• Arc Fatigue: The story moves at a very slow pace, with mixed reactions from readers.
• Base-Breaking Character:
  • Rias, largely because the story portrays her in a much more sinister light by using the Fanon concept that she allowed Issei to be killed by Raynare so she could resurrect him as her Pawn. The author does try to explain this by having Sona point out that Rias and several higher-echelon devils were afraid Issei might refuse to join her Peerage if she simply asked him; by having Rias actually feel bad about doing it; and that, since the story is told from Shirou's perspective, he might have misunderstood; but for some, it wasn't enough.
  • Kokabiel's Adaptational Heroism was equally liked and disliked by readers.
• Broken Base: The author's decision to push Issei to the sidelines has received mixed reviews.
• Growing the Beard: The plot didn't start to kick into high-gear until Kokabiel showed up, at which point things got deadly serious.
• Moe:
  • Koneko Tojou is a cuddly, mischievous little Cat Girl.
  • Ilya von Einzbern is just as Cute and Psycho as ever.
• They Wasted a Perfectly Good Plot: Issei having Karasuba as a sister is an interesting enough plot for its own story. However their relationship is not really given any focus, thanks to Issei getting Demoted to Extra and what we do hear about it is limited to second-hand exposition.