Born August 11th, 1977 in Hiroshima, Japan, same place as Suzuka and Riho. Her full name is Mikiko Mizuno (no relation to Yui).
She has been with BABYMETAL since the very start (she also worked with Sakura Gakuin, as well), and continues to do their choreography to this day. She is mostly known not just as BABYMETAL’s choreographer, but also Perfume’s, and has her own dance group, ELEVENPLAY. In 2018, a few of the dancers that joined BABYMETAL were from ELEVENPLAY. She also did the choreography for Suzuka’s previous group, Karen Girls.
She is one of the most successful people inside the BABYMETAL crew. Her biggest achievement is likely doing the choreography for the Japan part of the 2016 Rio de Janeiro Olympics Closing Ceremony. She was also planning the choreography for the recently finished Tokyo 2020 Olympics Opening and Closing Ceremonies. Sadly she left the project a few months ago due to several issues with the leadership, including some very sexist remarks. Just today the plan she had leaked, it would have included Perfume, Mario/Nintendo, Akira, and more. Too bad it did not end up happening.
To learn more about her, you can read this interview in Hedoban Vol. 6 [Purchase link] where she talks in depth about Road Of Resistance‘s choreography, and how much the girls had learned thanks to the experience overseas (interview is from 2015) and how that helped them to be better performers.
So if you enjoy any of BABYMETAL’s choreography, be sure to thank her.