Yagami Arian  

The Reaper, ヤガミ・アリアン

Arian Yagami was a soldier under Nelle Poe who fought for Mars independence during the Pan-Galactic War. He was part of a large battle and either survived alone or with very few others. He is known as "The Reaper" due to his destruction of RBs and his cold, efficient approach. Early in the series, he tells Elizabeth that he struggles to control his emotions.