Sebastian is Ariel's crab friend and court composer in Disney's The Little Mermaid.
Sebastian serves King Triton and is initially tasked with watching over Ariel. Although he often tries to enforce the king's rules, he becomes one of Ariel's strongest allies as the story develops. His formal title in Atlantica is composer, and his musical performances are central to the film.
The character is especially associated with “Under the Sea,” a lively song celebrating life in the ocean. Sebastian also sings “Kiss the Girl” during the attempt to help Ariel and Prince Eric fall in love.
A frequent mix-up is confusing Sebastian with Flounder, Ariel's fish companion, or Scuttle, the seagull who collects human objects. Chef Louis is another crab-related character, but he is a human chef who pursues Sebastian in a comic sequence.