Crude but not outright repulsive, Grimmjow is the sixth espada in Aizen's arrancar army which is ranked in terms of strength. His body is toned and mesomorphic implying that he's physically fit and well trained. He's tall with wide shoulders and a thin waist which reinforces his agility and proficiency on his feet. He wears a light jacket-vest and long robe-like pants. His clothing is lightweight so that they don't weigh him down or anchor him in combat.

His hollow hole is located at the lower center of his abdomen and the remnants of his hollow mask appears to have been removed going downward from the upper portion of his head and finally reaching his mouth. The mask, which appears to be in the curve of a smile, is nearly twice as large as Grimmjow’s actual mouth.

He generally desires to fight anything and anyone who comes in his way. Repeatedly, he chooses to disobey the orders of his superiors in order to find someone to fight. In many ways, Grimmjow is more self-ruling than the other espada because of his individuality and rash conduct. He is often independent and self-sufficient when it comes to making decisions. In other words, Grimmjow is a perfect example of an arrancar that never intended to stand by Aizen.

He often chooses to fight aloof to whether or not his opponent is stronger than him. He's cruel and callous, but is not interested in fighting weaklings. He would much rather fight formidable opponents. Weaklings, to him, are only a waste of time. His strongly believes in the concept of survival of the fittest. When he fights, he's determined to crush his opponent as severely as possible.