Clans: Ibaraki

A Dorei clan of De Clan, Ushuku of Orange Class is a member. He,his brother and father were seeking asylum in White Oak when Jiyu's parents were killed.

The father and older helped fight the Rogue Knights off where he could. Ushiku and his brother the only ones to see Jiyu awaken his Rhenze heritage. 

The Senshi that arrived only saw the end results, before Minashigo put the script on him. 

The Ibaraki clan are naturally fit and durable,  the excel in physical training. Karatairu comes natural to them and Yunatairu has to be very strong to effect them.

The Ibaraki clan all have a script placed on their Zai Star at birth. It is a control method used by the upper Clan(s). It allows them to be controlled at any moment.  They do not have to be in close proximity.

Centuries ago the Ibaraki were a powerful and feared clan. Due to their ability to become so physical formidable they could defend against Saino with sheer physical force and will.

The most legendary of them could actually counter element Saino with Karatairu and Kentairu. For this reason the clans formed together to destroy them,but their future Dorei clan desired otherwise.

That clan was De, they wanted to cultivate and harness the clan and invite them into an alliance. But due to the fear and hatred of the other clans,servitude was the only option.

Otherwise the clans would have been at war until they were all dead.