The magical girl Mitsuri, who is searching for her missing sister, transforms her bike using the power of her soul and competes in races against rivals. "Liddel Light" is the collective name for the bikes the girls ride. Mitsuri, who appears as a six-year-old in the first episode, grows one year older with each episode through the annual bike race battles, alongside her companions and rival magical girls like Kiyora, depicting the so-called "growing heroine" narrative.