Tomoko Miyaguchi (宮口 知子, Miyaguchi Tomoko, born August 17, 1975) is a Japanese retired professional wrestler, better known by the ring name Ran Yu-Yu (輝優優, Ran Yū Yū). Best known as a tag team wrestler, Yu-Yu held the JWP Tag Team Championship a record seven times, the Daily Sports Women's Tag Team Championship three times, the AAAW Tag Team Championship and the Oz Academy Tag Team Championship twice each and the International Ribbon Tag Team Championship and Wave Tag Team Championship once each, but also excelled in singles competition, most notably winning the JWP and Oz Academy Openweight Championships. She finished her 18-year career on December 9, 2012.