Ryuu Sen is one of the 100-Man Commanders of the Hi Shin Unit.
Ryuu Sen is a large man. Despite his obese look, he is quite muscular, as proven by his enormous strength. He has long hair tied in a top-knot and unusually small eyes and lips. His attire is that of a 100-man commander of Qin.
He is very determined to protect his family and home. This was the driving force pushing him forward in his first battle. When on winning streak very confident. His child was born 1 month before the Qin-Zhao conflict.
Ryuu Sen was recruited by Den Yuu becoming the 16th Squad Leader of a 5-man team within Shin's independent 100-man unit.Ryuu Sen at first felt nervous because it was his first battle. Shou Sa told the unit that Ryuu Sen’s first child was born a month before the war and he was worried. The whole unit started to feel uneasy. Shin got them back on topic. And explained what horrors will befall all of Qin if they fail. And that could also happen to his child. Ryuu Sen then banged his head into the ground, and told Shin he was ready. When they charge the Zhao, Ryuu Ssen single-handedly opened a path for them.
With the help of his strength the Hi Shin Unit eventually managed to get near the enemy HQ. General Fuuki maneuvered his HQ away from the Hi Shin Unit when suddenly 4th Army Commander Kanuo and 1000-man commanders Heki and Shou Kaku showed up and commenced battle against Fuuki's elite guards. This gave Shin the opportunity to slay Fuuki while the general tried to escape.
A few days later, the Hi Shin Unit was folded into the 4th army to hit the Zhao HQ with their whole army. They then charged the foot of the mountain to set up their HQ. They then saw that the Zhao had practically made it into a fortress. When they climbed Shin had Suu Gen and Shou Sa cover Ryuu Sen while he broke the fence. When they entered the Zhao started retreating. Den Ei notices that the Zhao were already long gone by the time they got there. And have moved their HQ and soldiers to a new location.
That night after taking the hill the Hi Shin Unit rested when all of a sudden Hou Ken broke into their camp and shortly followed by General Mangoku's soldiers. In that night raid, the Hi Shin Unit would lose many of its men from Hou Ken's own hands and while being chased down by Mangoku's army. Shou Sa even said that Ryuu Sen lost his whole squad. Eventually, the Hi Shin Unit would regroup and fold into Great General Ouki's main army.
He is three times stronger than Den Yuu and therefore a member of the Four Monster Squad.
- He was revealed to be a 100-man Commander in the chapter 251 side story.
- In the anime, Ryuu Sen is seen as a cavalry soldier.