This "sibling romantic comedy" revolves around Masamune Izumi, a light novel author in high school. Masamune's little sister is Sagiri, a shut-in girl who hasn't left her room for an entire year. She even forces her brother to make and bring her meals when she stomps the floor. Masamune wants his sister to leave her room, because the two of them are each other's only family.

Masamune's novel illustrator, pen name "Eromanga," 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 "Eromanga-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!

Yukihira Souma's dream is to become a full-time chef in his father's restaurant and surpass his father's culinary skill. But just as Yukihira graduates from middle schools his father, Yukihira Jouichirou, closes down the restaurant to travel and cook around the world. Although downtrodden, Souma's fighting spirit is rekindled by a challenge from Jouichirou which is to survive in an elite culinary school where only 10% of the students graduate. Can Souma survive?

How does the world look in your eyes? Papika and Cocona, the heroines of the story, hold the keys to open the door. When the two girls meet, their adventures in a different time and different overlapping dimension called "Pure Illusion" begin. Many things in Pure Illusion will stand in the girls' way on their search for the mysterious crystal called the "Shard of Mimi," an item that is said to grant any wish. However, when the girls find themselves in danger, the Shard of Mimi shines, and they are able to transform.

An overworked 24-year-old finally decides to live a little and create a bucket list, when a zombie outbreak hits the country.