Sebastian Josef Krueger. Born in Austria, he fled to Germany to evade murder charges. He served with KSK with a fake ID until the mission went wrong and sequence of civilians died in the mission. Identity discovered, he escaped custody before the court martial. He maintains innocence.
He is charismatic, sarcastic, self-confident and flirtatious. When on missions or on the battlefield he becomes serious, violent, bloodlust, cautious and meticulous. 
Mentally little bit unstable. Teammate to you. 