Marrow (Sarah), is a Marvel Comics character, associated with the X-Men. She is a mutant whose bones grow out of her skin and can be removed from her body, providing her with potential knives and clubs as well as body armor. As a child, Marrow first appeared in Cable #15 (September 1994) and was created by writer Jeph Loeb and artist David Brewer. However, Uncanny X-Men writer Scott Lobdell and artist Joe Madureira defined her powers and temperament.