The problem is the heroine is too earnest, and the demon lord is too circumspect. So when the heroine foils the demon lords plans, the combination of these traits make the heroine's actions very extreme (her followers and not helping her either).
@phil777 I actually like that quirk, and it leaves me super stoked for when she finally says his name because whether it's the persona or just here embarrassment holding her back she'll have overcome it.