Member of Poseidal's Elite 13 (No. 3). Despite his number, Giwaza is actually the head of the group, and outside of Poseidal is the highest ranked member of the Poseidal military.
Later in the series Poseidal decides to promote Olibee over him, which enrages him so much that he decides to rebel against Poseidal. He gathers a huge force including most of the Elite 13 and attacks Poseidal's capital at Sveto at the same time the rebels are. His forces are eventually wiped out and he is killed trying to escape from the battle.(Source: Wikipedia)