Sebastian Kempf is a German actor and voice actor known for his work in dubbing numerous anime series for the German-language market. He provides the German voice for the character Kamazo, also known as Killer, in the long-running series One Piece.

Kempf was born in Munich in 1995 and studied acting at the University of Music and Performing Arts in Stuttgart from 2015 to 2019. Following his theatrical training, he performed with ensembles at the Nationaltheater Mannheim and Schauspiel Stuttgart before transitioning into freelance work for film, television, and voice acting. As a screen actor, he has appeared in productions such as the Netflix series Biohackers, the feature film Oskars Kleid, and episodes of the ARD crime series Tatort and Polizeiruf 110.

In the field of anime dubbing, Kempf is recognized for taking over the role of Killer in One Piece, a character who is a member of the Kid Pirates and one of the eleven Supernovae. He is the fourth German voice actor to portray this character. His other prominent anime voice roles include Shuuhei Hisagi in Bleach: Thousand-Year Blood War, where he provides the second German voice for the character, and Philip Wittebane in the German dub of The Owl House. He also voices the character Mike in the German version of the animated series Skull Island.

Beyond his work in animation, Kempf is active in dubbing for live-action productions. He has provided German voices for characters in series such as For All Mankind, Bridgerton, High School Musical: The Musical: The Series, and The Lord of the Rings: The Rings of Power. He also maintains an ongoing career as a Hörspielsprecher, or audio drama performer, for outlets such as Bayerischer Rundfunk, appearing in productions like the science fiction series Mia Insomnia.