Comby

"♫You'll never be alone-y As long as you are combing...♫"

Comby is a comb-shaped Gem which Blue Diamond apparently makes use of when at her pool.

Appearance
Comby resembles a purple ornate comb. Whether or not she has willingly chosen to adopt a comb as her physical form or has simply been turned into one remains unclear. She also wears a lavender ruff. Her gemstone is located where her nose would be.

Trivia

 * While her name is not mentioned onscreen, Comby was named in the credits of Familiar.
 * Comby shares the same voice actress as Blue Diamond.