Rina Ikoma is from Yurihonjō, Akita Prefecture. In 2011 she applied for the Nogizaka46 auditions among 38,934 other girls. She became one of 56 girls who advanced to the final round and in August she was chosen to become one of the 36 founding members.
For Nogizaka46's debut single, "Guruguru Curtain", Rina was appointed to be one of the three centers in the title song's choreography. She became the only member who kept her center position in the second single, titled "Oide Shampoo". On February 24, 2014, a shocking announcement was made at the AKB48 Group Team Shuffle in 2014, that she would hold a position in AKB48's Team B. On February 26, 2015, it was revealed that Rina Ikoma was chosen to star in a live-action movie based on the Corpse Party series of video games.
A month after, on 26 March 2015, it was announced that she would be relieved of her concurrent position in AKB48. On February 21, 2016, it was announced that she became a model for Anna Sui in Asian regions. She released her first solo photo book Kimi no Ashiato on February 24, 2016.
It has sold 16,000 copies in a week, and ranked 1st on the Oricon weekly photo book sales chart. Unusually for a girl, Rina Ikoma likes to read comics for boys (shōnen manga), primarily the Weekly Shōnen Jump magazine. It started in the first year of middle school, when she was given the manga Gin Tama and became addicted to it.
Before that, in elementary school, she read what other girls read. Among her other favourite comics in the past she lists Naruto, One Piece, Sket Dance. Her recent favorites (as of spring 2012) are Blue Exorcist and Inu x Boku SS. Her favourite food is cucumber asazuke.
Her oshimen (number one favorite member) of AKB48 is Mayu Watanabe. Events Girls Award 2013 A/W Stages Subete no Inu wa Tengoku e Iku (AiiA Theater Tokyo, 1 October 2015 - 12 October 2015).
She is a member of the girl group Nogizaka46, and a former member of AKB48's Team B. She was the center member for Nogizaka46 first 5 singles, and she took the 6th center position for their 12th single released on 22 July 2015. She also recorded a solo song to accompany the single, becoming the first member of Nogizaka46 to do so.