He wore armor befitting his rank.
Dou Sei held a deep hatred for Shin and the Hi Shin Unit due to the defeat at their hands.
He participated in the Battle of Sanyou under the command of General Rin Ko. The lost suffered at the hands of the Hi Shin Unit created hatred and thirst for vengeance. He re-emerged in the Risei area along with 4,000 men as a staging point to reclaim the region of Sanyou.
After the loss, he held a grudge against Shin who killed Rinko. With Hyou Ki and Kan Ei, he engaged the weakened Hi Shin Unit with 1,000 men when ordered by Hyou Ki. He was killed by Den Yuu and his men were destroyed by the Hi Shin unit.