The Jactura are a group of families that in ancient times came together to perfect the practice of summoning demons. They have continued this tradition for centuries and are still prominent in modern times. Being founders of the nation of Dagara, all six families are quite wealthy and live in lavish estates.
Long ago, the country of Dagara was split into multiple warring states, with powerful families controlling pieces of the country and were constantly trying to claim more land to unify the nation. Eventually, a couple of families that controlled states in the northern forests decided that it was in their best interest to band together and pool their skills so that together they could unify the country under their names. The 6 families; Kagoro, Abricus, Larara, Belgior, Manoria, and Isca; allied their states and formed the Jactura. The Jactura was implemented to find a way to gain great amounts of power by piecing together all of their knowledge. They eventually developed a way to summon demons, and developed the skill over years of practice and honing the rituals. Using this power, they were able to have members of the families host these demons and become powerful soldiers. They were able to quickly overrun the neighboring states and eventually unified Dagara.
The families ruled Dagara for a long time until a period where the families began to become corrupt with greed as each family wanted to be the sole ruling line for Dagara. They began testing on civilians and siphoning money from the country to gain power. This lasted for until the father of Kygen Arvander ended it and claimed the ruling seat so that he may restore peace to Dagara. Kygen's father had an open heart and instead of denouncing the families he allowed them to atone for their corruption and maintain their statuses in society. The Jactura are now normal and harbor no foul feelings for the new ruling family, as they see it as a sign that their time to rule was coming to an end.
The Jactura, by using the collective knowledge of the 6 families, were able to gain access to the demon realm Bagorum. They developed a ritual named the Bagorum Calling in which they can pull a demon from its real and place them in a host. The host then goes through extensive training to maintain and control their demon. Through tradition, The Bagorum Calling is invoked when a member of one of the families turns 6 and is willing to undergo the ritual. While it seems that the host age is quite young, the age 6 is an homage to the 6 families that came together to form the Jactura as well as a way to give them ample time to train with their demon so that they become exceptional warriors.