Koike started a junior idol career with the DVD Big Brother at age 10, when she was in 4th grade. Koike Rina played Sailor Luna in the 2004 live-action version of Sailor Moon, Pretty Guardian Sailor Moon. She also played the role of Shizuka on the 2008 Kamen Rider Series, Kamen Rider Kiva. In early 2011 she starred in the short TV drama Onegai Kanaete Versailles, alongside visual kei metal band Versailles.
After graduating from Asia University in 2016, Koike took a two-year break from the entertainment industry to spend time studying English in New Zealand and Australia.
2022
2022
2021
as Mahiro Takasugi
2020
2020
as Hina
2017
2016
as Sakuya
2016
as Eri Yamaguchi
2015
as Aiko Machida
2015
as Sakuya
2014
as Sakuya
2014
as Yoko Kuroda
2014
as Arina
2014
as Mayu
2013
2013
2010
as 小林 めぐみ
2008
2008
as Shizuka Nomura
2008
as Shizuka Nomura
2008
as Shizuka Nomura
2008
as Shizuka Nomura
2008
as 野村静香
2007
2006
as Nagasaki Sayaka
2006
2006
2006
2003
as Luna Tsukino / Sailor Luna
1971
as Shizuka Nomura