"Lime-iro Senkitan: The South Island Dream Romantic Adventure" is a 12-episode anime series that blends historical fiction, romance, and supernatural elements. Set in the early 20th century, the story takes place on a fictional South Pacific island during the Russo-Japanese War. The narrative centers around Shintaro, a young man who becomes entangled in a mysterious and fantastical adventure after being shipwrecked on the island. He is rescued and taken to a girls' school, which serves as a front for a secret military base. The school is home to a group of unique girls, each possessing special abilities tied to ancient spirits known as "Shikigami."

The girls—Aoi, Karin, Karen, Sango, and Yukimi—are part of a covert unit tasked with protecting Japan's interests using their Shikigami powers. Shintaro, initially unaware of their mission, gradually becomes involved in their operations. As the story progresses, the group faces various challenges, including enemy forces, internal conflicts, and the complexities of their own emotions. The series explores themes of loyalty, duty, and the bonds formed between the characters as they navigate both their personal lives and the larger geopolitical tensions of the era.

The plot intertwines historical events with fantastical elements, creating a unique backdrop for the romantic and adventurous developments. Shintaro's relationships with the girls evolve over time, with each character contributing to the group's dynamics and the overarching narrative. The series balances lighthearted moments with more serious undertones, reflecting the challenges of war and the responsibilities borne by the characters. Through its blend of action, romance, and supernatural intrigue, "Lime-iro Senkitan" offers a distinctive take on historical fiction within the anime genre.