Rookie (Earth-5875)

"I need you to be strong - strong enough to do what you've never done in your life. Can you be strong enough to allow yourself to be... can you just be human?"

- - Rookie to Ghost

"Rookie" was a member of the UNSC Marine Corps under the command of "Ghost".

Biography
Rookie fought under the sergeant known as "Ghost" during the First Contact War. While she admired his leadership and the respect he inspired, she disliked his behavior, as he did not display any emotion and preferred to remain distant from her and the rest of the platoon. During an engagement against the Covenant, she was mortally wounded, and the rest of the platoon, sans Ghost, was killed. When she was dying on Ghost's arms, she had one final request, for Ghost to "be human".

Ghost was dispatched to the Inner colony Algolis during the Battle of Algolis, taking command of the Hades Corps. During the engagement, he stole a prototype exoskeleton in order to give time for the surviving Marines and civilians to escape the colony. He was eventually overwhelmed, and as he contemplated his newfound humanity, he uttered the code of the exoskeleton's self-destruct system: "Be human", fulfilling Rookie's wish.