Sergei

Оригінальне ім’я: セルゲイ

Sergei, known most often by his code name D, works for Ajou and is charged with special missions. He is very cold and aggressive, skilled at operating the PPOR robots and follows various military tactics. He also possesses superhuman strength and endurance, as a result of artificial enhancement. He is sometimes seen taking in Gel as a way to retain his strength. (source: Wikipedia)