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.

When lazy, erotic-game loving Mahiro Oyama is transformed into a girl by his younger scientist sister's experiments, he becomes determined to change back, only to recognize that with his new opportunity, he may want to turn his life around.

Famous racehorses that have left behind worthy legacies, unique as they can be, are reincarnated as horse girls in a parallel world. In this life, they start their journey anew as they continue to race and perhaps relive the success they once lived through.

Aspiring to become the best racehorse in Japan, a horse girl named Special Week moves to Tokyo to enroll in the Tracen Academy—an institution that nurtures horse girls like her to become better racers. There, Special Week witnesses the sophisticated running style of Silence Suzuka and is inspired to become a racer like her. Shortly after, Special Week finds herself recruited into Silence Suzuka's team, Spica. From there, she begins her path to the top—one lap at a time.