Maou-sama ni Oshieteageru
魔王さまに教えてあげる · まおうさま に おしえてあげる
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
Sarah is a young girl who lost her homeland in a conflict between people. After she is ordered by her mother to run away, she desperately wandered the mountains, becoming exhausted and losing consciousness. There, a beautiful young man with refined attire appeared... Sugar, a demon. And then, several years passed... A spirited girl who dislikes humans, Sarah, and a kind-hearted demon lord who loves humans, Sugar. A fantastic love story between a non-human and a girl, brought to you by these two complete opposites! (Source: Ichijinsha, translated)
Source: AniList
External databases: AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections