Rolo never had any sort of childhood. He was essentially born and raised within the Geass Order, trained since birth to be a killer. He never experienced any sort of love or attachment beyond a few children he might call "friends" - however, he would think nothing of killing them, should he be given the order.
Hunt for C.C.
Rolo was given a special assignment by V.V., the director of the Geass Order - find the illusive C.C. while monitoring Lelouch vi Britannia. He was given the alias "Rolo Lamperouge" and began attending the Ashford Academy.
Lelouch was a Britannian prince who had taken up the name of "Zero" as a rebel fighting for the freedom of Japan. Lelouch's memories were wiped by Emperor Charles zi Britannia, and his memories were changed to erase memories of his time as Zero, knowledge of his own Geass powers, and memories of his sister, Nunnally vi Britannia, were replaced by false memories of Rolo.
Lelouch and Rolo lived a seemingly peaceful life for one full year. Rolo and Lelouch even started to bond as "siblings." Rolo was overcome by feelings of family and friendship that he had been denied his entire life. Rolo even received his first birthday present, a locket originally intended for Nunnally, which became his most prized possession.
Powers and Abilities
Rolo possesses the power of Geass, and has since he was a child. Rolo's Geass power is the ability to "stop time" in a limited area; however, it was proven that he cannot truly stop time, but rather his victim's perception of time. He usually uses his abilities to perform assassinations His Geass sigil is shown in his right eye.
Because his powers only effect his victim's perception, objects and projectiles are not affected. For example: if somebody shot him, he could not stop the bullet.
However, Rolo was deemed a failure. His powers are defective: his heart stops whenever he slows time, causing him to clutch his chest in discomfort for the duration, and will visibly show exhaustion after repeated uses. Therefore, he risks his life every time he uses his Geass.
While Rolo is a practitioner of Geass, he is knowledgeable in the use of weapons, at least to some extent. He knows weak points on the body that would cause the most damage, or cause death. Typically, he goes for quick kills. As a child, he knew how to handle a gun.
He did become accustomed to using a Knightmare Frame - the Vincent, a prototype mass production version of the original Lancelot - and knew ho to use it somewhat effectively. However, he relied on his powers to give him the edge, and had difficulty against superior skill or good strategies.