Maren Rainer is a German voice actress born in Munich on February 16, 1983, who has built an extensive career in dubbing, lending her voice to numerous characters in anime, animated films, and live-action series. She began her voice work at the age of five, securing small speaking roles through her father, actor and voice actor Leon Rainer. Her first leading role in an anime series came as the young Annette in The Alps Story: My Annette, which aired from 1995 to 1996.

Rainer's notable work in anime includes providing the German voice for several key characters. She is the voice of Michiru Kaioh, also known as Sailor Neptune, in the Pretty Guardian Sailor Moon Crystal series starting from its third season, and reprised the role in the films Pretty Guardian Sailor Moon Eternal and Pretty Guardian Sailor Moon Cosmos. She voiced Rin Asougi, the immortal private investigator, in the series RIN - Daughters of Mnemosyne. Her other prominent roles include Asuka Ootorii in Magical Girl Spec-Ops Asuka, Tashigi in the film One Piece Stampede, and Zena in the animated film First Squad - The Moment Of Truth. She also contributed to Studio Ghibli films, voicing a character in Kiki's Little Delivery Service and Shiho Tsukishima in Whisper of the Heart.

Beyond anime, her dubbing portfolio is extensive and varied. She has been the German voice for actresses such as Scarlett Johansson in films like Lost in Translation, Shenae Grimes in the series 90210, and Billie Piper in Doctor Who. She has also voiced characters in major animated productions, including Wyldstyle in The Lego Movie and its sequel, Barbie in Toy Story 3, and the water fairy Silvermist in the Tinker Bell film series. In addition to her work as a voice actress, Rainer has also been active as a dubbing scriptwriter, writing German dialogues for series such as In Plain Sight and the Disney sitcom Meine Schwester Charlie. Her work also extends to audiobook and radio play productions.