Emil Castagnier

His parents were killed by Lloyd Irving the main protagonist in the original Tales of Symphonia. He is portrayed as a coward but promises to protect Marta Lualdi the bearer of the Ratatosk Core by forming a contract with the Lord of Monsters Ratatosk thus making him the Knight of Ratatosk. He receives the strength to fight against monsters through this contract making his voice deepen his eyes turn red and his attitude bolder. In the duration of this phase Emil is more violent and bloodthirsty which is why some call him a monster. This form is later on called quotRatatosk Modequot. His goal is to help Marta hatch the Centurion Cores and ultimately avenge the death of his parents. Source: Wikipedia