Rei

Naoi Rei, known by her stage name Rei, was born on February 3, 2004, in Nagoya, Aichi Prefecture, Japan. She grew up with a passion for the arts — drawing portraits, collecting figurines, and following K-pop music closely. From a young age she was drawn to Korean pop music and harbored a dream of becoming a K-pop idol, a highly unusual aspiration for a child growing up in Japan at the time. In April 2018 she passed the Loen Friends Global Audition held in Japan and was accepted into Starship Entertainment's training program.

Rei relocated to South Korea alone in May 2018 at just fourteen years old — a remarkable and courageous decision. She quickly became proficient in Korean, earning the affectionate nickname "Kim Rei" from her IVE groupmates for speaking the language so naturally. She attended the School of Performing Arts Seoul (SOPA) and later enrolled at Chung-Ang University's Theater and Film Department. She trained for approximately three and a half years before debuting.

Rei was revealed as the fifth member of IVE on November 5, 2021, and debuted alongside the group on December 1, 2021. She quickly established herself as IVE's main rapper, her distinctive tone and confident delivery providing a sonic texture to the group's sound. She has personally written rap verses in Korean, Japanese, and English for IVE's releases. In April 2023 she briefly took a hiatus due to health concerns (heart palpitations) but returned to full activities on May 26, 2023, and has been fully active since.

Rei carries the quiet intensity common to INFJs — thoughtful, creative, and deeply invested in craftsmanship, whether in her rap writing, her meticulous portrait drawings, or her Sylvanian Families collection. She is described by members as the most artistically inclined, and her transition from a Japanese hometown to the pressures of the Korean idol industry without family nearby speaks to a strong and self-directed character. Fans and members alike note how seamlessly she adapted culturally, making her bilingual proficiency and cross-cultural identity a key part of her public persona.