Masamune's novel illustrator, penname “Ero Manga Sensei,” draws extremely perverted drawings, and is very reliable. Masamune had never met his illustrator, and figured he was just a disgusting, perverted otaku. However, the truth is revealed … that his “Ero Manga Sensei” is his own younger sister! To add to the chaos that erupts between the siblings, a beautiful, female, best-selling shoujo manga creator becomes their rival!
(Source: Anime News Network)
