Reiko Takagi is a Japanese voice actress and narrator born on November 26, 1973, in Osaka Prefecture, Japan. She is affiliated with the talent agency Sigma Seven. After graduating from the Yoyogi Animation School's voice actor course, she began her career in the mid-1990s. Her early work included minor roles in series such as El-Hazard and Slayers Try, with one of her first notable recurring parts being the young Kain Blueriver in Lost Universe in 1998.

Takagi is known for her versatile vocal range, frequently portraying young boys, teenage girls, and small creatures. She gained prominence in the early 2000s with major roles like Kaolla Su in Love Hina, Yoshitaka Waya in Hikaru no Go, and Yamato Daiwa in the Battle B-Daman franchise. She has also been a consistent presence in long-running series, voicing Hiyori Sarugaki and Rurichiyo Kasumiōji in Bleach, Tadase Hotori in Shugo Chara!, and Maki in the Minami-ke series.

Her filmography includes many of the titles listed in the query. In the La Corda d'Oro franchise, she voiced the protagonist Kahoko Hino in Primo Passo and Secondo Passo, and later Kanade Kohinata in Blue Sky. She played the dual roles of Sakura Kusakabe and Minami-san in the Bludgeoning Angel Dokuro-chan series. She also voiced Nobunaga Asakura in both seasons of Haruka Nogizaka's Secret, Pakase in the MonHun Nikki Girigiri Airū-mura series, and Sei in Hime Chen! Otogi Chikku Idol Lilpri. In the Patalliro Saiyuki! series, she took on the role of Genjou Sanzou Houshi, also known as Maraich. Other credited roles include Airi in Kikō Heidan J-Phoenix, Shibiretta in Yes! Precure 5 GoGo!, Tetsunoshin in Wan Wan Serebu Soreyuke! Tetsunoshin, Ken-chan in Yamibo - Darkness, the Hat, and the Travelers of the Books, Tōko Gorōmaru in Mushi-Uta, and Kōta Tatsumi in Battle Spirits: Heroes. In the One Piece franchise, she voices the character Jewelry Bonney, appearing in both the television series and the film One Piece Stampede.

Beyond anime, Takagi has an extensive career in video games. She is well-known for providing the Japanese voice of Cassandra Alexandra in the Soulcalibur series. She has also performed narration for various television programs and commercials. Her contributions to the industry are marked by her longevity and the breadth of characters she has brought to life across several decades of animation and gaming.