Sagiri Izumi
The younger step-sister of the protagonist. Shut in her room all day, she was secretly the illustrator for her brothers light novels and is popular on the web, though nobody knows that she is actually a 12-year-old girl.
Sagiri was taught to draw by her mother at a young age, and by the time she was around the age of nine, she became Masamune’s illustrator. A year before the events of the novel, Sagiri met Masamune, though she didn’t realize that he was the author she was working with despite the similar names. After her mother died, she temporarily stopped drawing and going outside. After seeing a live video of someone drawing images and getting a response, Sagiri became interested in live video feeds and started drawing images on a camera disguising her face and voice so that nobody would recognize her or learn about her. She eventually started to interact with people who saw her video feed (while still disguised). At some point, Masamune was too busy to cook and she chose to go hungry rather than go outside her room to get food.