Lelouch
Lelouch vi Britannia serves as the main character in the side stories Code Geass: Oz the Reflection and Code Geass: Lancelot & Guren as well as Code Geass: Lelouch of the Rebellion and Lelouch of the Rebellion R2. He defeats a lot of people who are much stronger than him thanks to his brains. Lelouch is notoriously stoic and difficult to provoke; but, if his sister Nunnally's safety is in danger, he is willing to put everything on hold and run to her aid.
Lelouch is renowned for having a stern demeanor. Despite the fact that he would have an easy time with his high level of intelligence, he never cared about academics and thought the whole thing was ridiculous. Lelouch is a very strategic and cold warrior. If it is necessary to accomplish the goal, he is willing to sacrifice both military and civilians.
Lelouch wanted to topple Britannia because he wanted to give Nunnally a better life. Even his comrades were left behind in order to save Nunnally. Lelouch has repeatedly demonstrated how much he loves his sister. Lelouch's use as a diplomatic tool was abandoned when Britannia finally developed its Knightmare Frames fleet and decided to invade Japan to seize control of the Sakuradite mines. Out of concern for their safety, Lelouch hid their true identities and sought assistance from the Ashford family, his mother's allies.
Anime: Code Geass