Kotoko Imai is a third-year junior high school student and a main human protagonist in the Mewkledreamy Mix! anime. She is the senior of Yume Hinata and forms a Dream Partner pair with the plush-like being Suu. Academically she stands at the top of her grade, and she serves as the president of the computer club. Her character is energetic, humorous, and occasionally playfully mischievous, which complements the more reserved personalities around her. She is also noted for being naturally attentive and good at looking after others.

Her central motivation is a vision of a society where humans and robots live together peacefully. This drives her to dedicate much of her time and talent to robotics, and together with her club members she builds and refines robot creations. Her first successful robot is called Kotokoto, a project that reflects both her technical skill and her caring nature. Throughout the series she persistently works on improving her robotic inventions, making this an ongoing element of her personal growth.

In the story she participates alongside the other Dream Partners in entering dreams through Dream Synchro, fighting nightmare creatures, and collecting Dreamy Stones. Her role weaves together her school life, her bond with Suu, and her friendships with fellow Dreamy Mates such as Yume, Maira, Asahi, and Tokiwa. Through these experiences she learns to balance her ambitions with teamwork and compassion. Her notable abilities include exceptional academic performance, leadership in the computer club, advanced robotics knowledge, and the power to perform Dream Synchro with Suu, which allows them to traverse dream worlds and confront threats born from negative emotions.