The protagonist, a Japanese man, wakes up in an unfamiliar world, finding himself in a grassy plain. He is discovered by an elf named Rustil Drake, a stern but kind warrior who offers him water. The protagonist, who has inexplicably retained his Japanese consciousness and the ability to understand and speak the local language, realizes he has been transported to another world. He discovers he has also become an elf, with pointed ears, though he lacks significant magical ability. Rustil, a skilled spear wielder, takes him under her wing, and they join a merchant caravan.
The caravan travels to a town, where the protagonist, now calling himself Lyle, is shocked by the primitive architecture and lack of familiar technology. Rustil, despite her warrior nature, shows him great kindness, even embracing him to calm his anxiety. Lyle learns that elves are common in the "Kei Empire" and that the empire was founded 400 years ago by a legendary figure named Arc Kei. He also learns that the empire is in a state of decline, with widespread corruption and famine, reminiscent of China's late Han Dynasty.
Lyle decides to travel with the merchant caravan to gather information. During his travels, he learns that women in this world are often strong and hold positions of power, and that magic is primarily used for physical enhancement. He also discovers he has been de-aged to around 14-15 years old and has a talent for calculation, though he lacks literacy skills.
Upon arriving in the capital city of Rand, Lyle seeks employment and eventually finds an opportunity to become a tutor for Lidia Barca, a remarkably intelligent ten-year-old prodigy. He uses his knowledge of Earth's science, such as the heliocentric model and gravity, to impress her. Lidia, despite her young age and stoic demeanor, is intrigued by his unique knowledge. Lyle is hired as her tutor, with the condition that he keep his knowledge secret and teach her three times a week. He also learns about the political landscape, including the ten corrupt officials who effectively rule the empire and the existence of beastmen to the north.
Lyle begins to gather information about prominent figures who might align with historical figures from the Three Kingdoms period of China. He hears about Ilhelmi Roen, a powerful and notoriously promiscuous female baron, and Karma Talk, a rising noble who has established peace with the beastmen. Lyle suspects these figures might be counterparts to historical warlords like Cao Cao and Dong Zhuo, and he realizes that if his knowledge of history proves accurate, the empire is heading towards a devastating civil war. He continues to gather information, hoping to find a way to survive and potentially use his knowledge to his advantage, while also maintaining contact with Rustil. He also learns about the existence of a legendary strategist named Liu, who is associated with the beastmen.
