Kawaguchi Yurina

 (川口ゆりな) is a former member of X21. As of 2021 she is confirmed to be competing in MNET's girl group survival show, Girls Planet 999.

History
She joined X21 in April, 2016 and was among the final lineup when the group disbanded. In May, 2021 she was spotted in South Korea and was identified as a possible contestant on MNET's girl group survival show, Girls Planet 999.