Eromanga Sensei (エロマンガ先生) is a Japanese light novel series written by Tsukasa Fushimi and illustrated by Hiro Kanzaki. ASCII Media Works has published nine volumes in the series under their Dengeki Bunko imprint since December 2013. A manga adaptation illustrated by Rin began serialization in Dengeki Daioh in May 2014. An anime adaptation produced by A-1 Pictures premiered in April 2017.
The story centers around high school student Masamune Izumi who loves writing light novels. Having no artistic skill himself, Masamune always got his novels illustrated by an anonymous partner using the pen name "Eromanga Sensei", who is known for drawing questionably perverted images despite being extremely reliable. In addition to balancing his passion and school, Masamune is also stuck with taking care of his only family member—his younger sister Sagiri Izumi. A hikikomori by nature, Sagiri shut herself in her room for over a year and constantly bosses Masamune around despite his attempts to get her to leave her room. However, when Masamune inadvertently discovers that his anonymous partner had been Sagiri all along, their sibling relationship quickly leaps to new levels of excitement, especially when a beautiful, female, best-selling shōjo manga author enters the fray.