Rina Koike (小池 里奈, Koike Rina?) (born September 3, 1993, Tochigi Prefecture, Japan) is a Japanese actress and idol affiliated with Very Berry Production.

Koike started a junior Idol career with the DVD Big Brother at age 10, when she was in 4th grade. Koike also works for Very Berry Production as a model. Koike Rina had a role on the live-action version of Sailor Moon, Pretty Guardian Sailor Moon. She plays the character Sailor Luna, as Luna transforms to a young girl later on in the series.

She also co-hosted the Pretty Guardian Sailor Moon Super Dance Lesson, on which she teaches the audience three different dances along with co-stars Miyuu Sawai and Myū Azama . These dances loosely follow line dancing. Sawai plays as Sailor Moon and Usagi Tsukino. Azama plays as Sailor Jupiter and Makoto Kino. Sawai and Azama wear special dance-costumes, but Koike is left out, wearing her everyday costume from the show.

Koike has now released a photo collection titled "Innocence."

She also played the role of Shizuka on the 2008 Kamen Rider Series, Kamen Rider Kiva.

Source: Wikipedia

(And again, user Stray is amazed by the magical information box!)