After their parents' tragic passing, Sagiri Izumi isolates herself as a recluse, disconnecting from her step-brother Masamune and the outside world. Meanwhile, Masamune supports their fractured family by crafting light novels, unbeknownst to him that his lewd illustrator, Eromanga-sensei, is closer than he ever imagined. As they navigate the complexities of the publishing world together, new hurdles arise, testing their bond and resolve. Eromanga-Sensei intricately weaves the tale of their evolving relationship and joint quest for success, all while Sagiri wrestles with revealing her hidden identity to society.