Grisaille (sometimes called Gray) was a member of the Spectrum Siblings, however he was created by Mr. Black, but not with Dame White. Because of this, he is disliked by most of the family, including his step mother. He acts as the primary agent to Mr. Black, although he punishes him for whatever excuse he could think of.
In truth, despite having the same traits as the family, he loathes his father and step-mother, and is eager to destroy the entire family.
Although he lacks the resources that Indigo has, he is more intelligent and personally powerful.