Mirai Asahina is a thirteen-year-old girl living in the ordinary human world, about to enter junior high school at the beginning of her story. She comes from a loving family with her mother Kyoko, father Daikichi, and grandmother Kanoko, who gave her a cherished stuffed bear named Mofurun. Mirai is an energetic, curious, and playful girl with a strong fascination for magic and a boundless sense of wonder. Her cheerful and optimistic nature is her defining trait, allowing her to see the bright side of even difficult situations and inspiring those around her. She is also intelligent and diligent, applying herself enthusiastically to her studies at the Magic School in the parallel Magic World. Her primary motivations are to deepen her understanding of magic and to earn the admiration of her close friend and partner, Liko Izayoi. She is deeply loyal and caring, especially toward Liko and Mofurun, and will not hesitate to put herself in harm's way to protect them.

In the feature film Wonderful Precure! The Movie! Exciting ♡ An Epic Adventure In The Game World!, Mirai appears as a supporting character alongside Liko and their fellow Cure, Kotoha Hanami. The story follows Komugi, Iroha, and their friends as they are pulled into a video game world. Mirai and the other veteran Cures join the adventure to help the newer heroines navigate the challenges of the game and uncover its secrets. Her role is to offer guidance, encouragement, and combat support, using her experience to bolster the team.

Mirai’s most important relationship is with Liko Izayoi, a serious and studious witch from the Magic World. Despite their contrasting personalities, they form a strong partnership and grow closer over time. Mirai also shares a deep bond with Mofurun, her beloved teddy bear who becomes a key item in her transformation. Her friendship with Kotoha, the younger Cure Felice, shows her protective and nurturing side. Throughout her own series and subsequent appearances, Mirai matures from an excitable novice into a more capable and responsible heroine, yet she never loses her infectious optimism and love for adventure.

As Cure Miracle, Mirai transforms using the phrase “Miracle・Magical・Jewelryle!” alongside Liko and Mofurun. Her magical powers are centered on light and life, symbolizing hope and positivity. In her base form, she wields a wand born from the Tree of Staff, topped with a heart-shaped jewel. She can access different style forms such as Dia Style, which allows her to cast multiple spells in battle. Along with Cure Magical, she can perform the combined attack Diamond Eternal. She also has access to Ruby, Sapphire, and Topaz styles, each offering unique techniques. Her abilities grow through Linkle Stones, enhancing her magic and teamwork. Cure Miracle’s vibrant design and radiant energy reflect her role as a beacon of hope, inspiring others to believe in themselves and the power of friendship.