Yoko Arai is a Japanese retired professional wrestler better known by the ring name Yoko Bito . Bito initially made her in-ring debut in December 2010 for World Wonder Ring Stardom and quickly became one of the most popular wrestlers in the promotion, until announcing her retirement from in-ring competition in November 2012. Bito came out of retirement and returned to Stardom in April 2016, and returned to the ring in June of that year, before retiring again in December 2017.

World Wonder Ring Stardom , often referred to simply as Stardom, is a Japanese joshi puroresu or women's professional wrestling promotion based in Nakano, Tokyo, Japan. Stardom was founded in September 2010 by former All Japan Women's Pro-Wrestling (AJW) co-producer Rossy Ogawa, retired professional wrestler and mixed martial artist Fuka Kakimoto, and former AJW veteran professional wrestler Nanae Takahashi. Stardom is currently owned by Japanese entertainment company Bushiroad, making it the sister promotion of New Japan Pro-Wrestling (NJPW).