At the contrary of the first season, Suzaku becomes a dark character, he's always serious and sad. After Euphemia's death, his only reason is the revenge.
He became Knight of Seven thanks to the help he gave to the Emperor Charles, when he brought Lelouch to him. He continues to fight for Britannia and for his goal: becoming Knight of One, in order to gain the Area 11 as his own land. Even if he hates Lelouch, he comes back to school to see if he gains his memory or not. He's always happy and social with his friends, but when needed, he turns to be serious.
After the Black Rebellion, he took with him the cat Arthur and Nunnally, who is trying to use for his sake.
He continues to pilot the Knightmare Frame Lancelot.