Jun’ichiro Kagami is a hardcore otaku who spends his days at home working on his anime website, much to the frustration of his sister Suzune. She forces him to take a job as a substitute physics teacher at his old high school, hoping it will make him engage with the real world. Despite his obsession with games, manga, and anime, Jun’ichiro proves to be a surprisingly dedicated and creative teacher. He uses his otaku knowledge to inspire his students in unconventional ways.

At just 17, Jun’ichiro made waves in the scientific community by publishing a groundbreaking paper on teleportation technology, inspired by Doraemon’s “Anywhere Door.” Though ridiculed at first, his theory remains unproven—and unrefuted—leaving open the possibility that humanity might one day achieve such technology. Despite offers from top research institutions, Jun’ichiro claims to suffer from “YD,” a condition that only allows him to do what he truly wants, leading him to reject prestigious opportunities.

However, after teaching for a while, he’s persuaded by Koyomi Hiiragi to join her university. Balancing his teaching duties with his passions, Jun’ichiro finds unique ways to connect with his students—whether through competitive games, personal mentorship, or his unorthodox teaching methods—helping even the most withdrawn students open up.