Ayumi Nagashii is a Japanese voice actress and former live-action actress. She is best known as the earlier stage name of the prolific voice actress Ryoka Yuzuki, under which she has built a substantial career in anime and video games. Born on January 10, 1974, in Anjo, Aichi, Japan, she began her entertainment career as a teenager using the name Ayumi Nagashii, primarily working in live-action films and videos. After a period working under other stage names, she eventually settled on the name Ryoka Yuzuki around November 1998 and has since focused almost exclusively on voice acting. She is currently affiliated with the talent agency 81 Produce.

During her time working as Ayumi Nagashii, she took on several roles in anime, including the part of Rie in the 1999 video anime Tokyo Babylon 1999 and the role of Tetsuko, the obsolete robot maid, in the surreal comedy series Super Milk-chan. After transitioning to the name Ryoka Yuzuki, she achieved widespread recognition for a vast number of major voice roles. Some of her most famous characters include Ino Yamanaka in the long-running series Naruto and Boruto: Naruto Next Generations, Satsuki Kiryuin in Kill la Kill, Shizuka Hiratsuka in My Youth Romantic Comedy Is Wrong, As I Expected, Minagi Tohno in Air, and Eruru in Utawarerumono. Her other prominent anime roles include Shamal in the Magical Girl Lyrical Nanoha series, Haruka Suzushiro in My-HiME, Arcueid Brunestud in Carnival Phantasm, Memetchi in Tamagotchi, Oriana Thomson in A Certain Magical Index, and Tokiko Tsumura in Buso Renkin.

Throughout her extensive career, she has appeared in many series that have multiple installments or spin-offs, demonstrating a pattern of long-term collaborations with specific franchises. Beyond Naruto and Boruto, she has reprised roles in numerous sequel series and films for properties like My Youth Romantic Comedy Is Wrong, As I Expected, Magical Girl Lyrical Nanoha, Trinity Seven, and Queen's Blade. Her notable achievements include a career that has spanned over three decades, transitioning successfully from live-action to voice acting, and becoming a highly recognizable talent in the industry. She has voiced characters in some of the most popular and enduring anime franchises of the modern era, contributing to series that have gained international fame such as Kill la Kill, the Naruto metaseries, and Cardcaptor Sakura, where she voiced Nakuru Akizuki.