Saburou's just your average high school kid—not exactly passionate about Japanese history, to be honest. So when he mysteriously gets transported back to Japan's Sengoku period, he's pretty much out of his depth. That changes fast when he crosses paths with Oda Nobunaga, the real deal, who notices they're practically identical. Nobunaga sees an opportunity and basically asks Saburou to impersonate him.
The setup's pretty clever: Saburou's got his high school history textbook on Nobunaga, which becomes his unlikely survival guide. He leans on it to figure out what's supposed to happen next and how to pull off this whole "becoming a legendary warlord" thing. It's as makeshift as it sounds, but it works well enough to keep him alive and moving through the events that shaped Japanese history.
Content compiled by AnimeList.moe from publicly available sources.
