Ichikawa Clan

The Ichikawa clan claims its origins to the swampy marshlands to the southern edge of Waterfall Country.  It was even there that their name--meaning 'one river'--is derived.  It was in this terrain that was perfect for a variety of species that they would begin their study of plant and animal life even decades before the discovery of chakra and the introduction of the modern day ninja.
They had started early to find ways to adapt the local flora and fauna to suit their needs.  Cross breeding plants to get desired results ranging from a new color all the way up to a better crop.  Taming animals and even cross breeding them.  In the more extreme cases even voluntary infection of parasites and pathogens in controlled environments for forced evolution.
A majority of these practices had fallen into disuse when the first of their line had taken to the profession of a ninja.  A few of the more extreme and more useful rewards had remained though; primarily a symbiotic parasite bred to co-exist in the Ichikawa member's body for their entire life time and potentially beyond.
Despite ninja training they had remained mostly supplemental in combat.  Their more inventive members devising new seals and designs on the Six Realm's initial seal.  Furthermore, with the parasite in mind they even delved into the healing arts.
After multiple wars and changing borders the Ichikawa clan is but a shadow of its former self.  Primarily supplemental and passive methods had been changed to an extreme that many of their members would even lead lives of criminals and vagabonds with only a handful finding themselves in the service of a ninja village.
As a means of expediting the training process and ensuring a thorough curriculum Ichikawa generally make use of their fallen comrades.  With the seals laid on their bodies keeping their souls from moving on to the afterlife.  Only when willing will they implant these souls--not unlike a Jinchuuriki-- their children and newborns.
This allows the adults to get training done at an exponential rate.  A second in the real world could be hours in the mind's realm.  The sharing of minds even allowing almost a direct link from person to person.  In this way even the youngest child with enough skill could learn every single one of the clan's jutsu before graduating from the academy.  To this end they can even learn every jutsu that the clan member sealed into them knew.
These practices allow each clan member freedom to pursue their own avenue of training on their own time while in the world
==History==
The early days of the Ichikawa clan are largely shrouded in mystery.  The family themselves hoping to keep all but the basics shrouded in mystery. These were dark times early in the history of the modern world with the world torn apart by in-fighting.  It was kill or be killed and for the Ichikawa family this meant desperation.  They had no gifts of their own or the resources to combat the larger and far stronger families.  They instead chose to resort to the darkest and most forbidden of things.  To tear apart bodies and rend souls twisting people and things into a shadow of its former selves.  
In their minds this was necessary for the survival of their line and name.
It was only a matter of time before they grew bold. They thought of things beyond self defense.  They wanted to expand their influence.  To drive fear in the hearts of anyone preemptively that may wish harm upon their family rather than be some forgotten foot note in the history books.  Even more they wanted to use the fallen of other clans to increase their power. It was even rumored at one point it was the research they made at this time that eventually evolved into the technique later known as Jiongu.
Their leader was a man who simply referred to himself as Akai ō.  His true name long since lost to history as much as his true face.  He had unlocked the secret to not only moving on using the clan's techniques but to also maintain control.  To leap from one generation to the next in the bodies of volunteers to further the cause; the best of the best in the clan until it expanded.  Akai ō started stealing bodies from captured individuals and twisting them.  It was his hubris that brought the downfall of the clan.  His overreach incited the wrath of not just one but all of the major clans.  The Ichikawa clan stood no chance and they were completely decimated.  
The few that escaped through the efforts of Akai ō had enough of the blood shed.  They knew their only hope of survival was to hide and be forgotten and let the rest of the world pass them by.  To vanish into the deepest and darkest swamps that no one wanted to touch.  And,they knew, that they couldn't do it with Akai ō at the helm.  
Even in his weakened state they knew they couldn't kill him. The bloody “king” had contingency after contingency in place to ensure that he would not pass on until he wished it.  They wouldn't feel secure even if he had passed on; a superstition having formed that even that wouldn't keep him down.
In their fear they instead bound him.  Tighter and tighter in ever increasing layers in seals that grew stronger with every generation even long after the family forgot the true reason for such a task.  They were little more than airy rumors to put the children to sleep at night like tales of the boogeyman.  
As nations formed and grew they kept their reclusive nature. Keeping to the swamps relocating only enough to station themselves within the border of Takigakure.  They provided their limited services to the local nation and supplied them with ninja only in a limited capacity; as much as they could in turn gain assistance from Taki.  It is here that they remained trying to better themselves in the arts of medicine and fuuinjutsu.
==Information==
The Ichikawa appear very unassuming.  They are not an exceptionally large or wealthy family but one of great health and physical prowess.  There's virtually no obesity or signs of other health issues and all are long lived by human standards.  Most stand on the taller end of the spectrum with even the shortest of males usually around 6'0” as an adult and females just 2-3 inches shorter.  They are usually built fairly stout.  They bear tanned skin, brown or green eyes, and brown hair. 
The most distinguishing features are the excessive use of tattoos and body piercings.  The process starts from the day that they are given the soul of their ancestors as a means of covering up and disguising the Fuuinjutsu that covers their bodies.  A s they grow older and more skilled the black scrawls of seals grow and so do the tattoos to cover them.  The initial few are decided by the family and represent the specific bloodline.  Beyond that they're ultimately an expression of the individual clan member.  
The piercings are both decorative and functional.  Their locations are keyed to acupuncture points.  The boosts gained from this are negligible until the clan member is capable of utilizing specific jutsu later in life.  They composition of the piercings vary from person to person but is almost always made of some conductive material.  Silver is preferable given its antiseptic properties.  A few have resorted to odd synthetic materials grown in the workshops of the clan.
==Abilities==
The core of the Ichikawa clan's abilities is their skill with Fuuinjutsu and the artful way they're able to twist the markings in a variety of way.  Each member of the clan is introduced to this from birth.  From their first moments in this world they are branded both body and soul.  Even at the most basic level this provides some degree of protection as it locks the individual's soul down preventing tampering, removal, or even destruction unless the seals can be bypassed.  It even keeps chakra in place keeping some—not all-- from being removed from techniques that could otherwise kill a person by absorbing their chakra.  
The second layer of these seals comes into effect when the clan member is introduced to their mentor.  The Ichikawa make use of their fuuinjutsu and inspiration from the process to create Jinchuuriki to implant long dead Ichikawa into the newer generations.  The method of choosing a recipient for each mentor varies and how long a mentor stays around or how many times they take on a new host will also vary. That said the Ichikawa are not attempting to stave off death with these techniques from rather improve each new generation more than the last. To that effect the seal that places the Mentor into the Host has several layers of protection that limits the interaction between the two unless the Host voluntarily—with enough training and knowledge-- removes some of these safeguards.
The first function of the defensive layer prevents the Mentor from gaining control of the Host.  As these seals were intended to hold and subjugate some of the most skilled practitioners of Fuuinjutsu it's virtually impossible for the Mentor to exert any control at all over their host even in states of altered state, incapacitation, or unconsciousness.  This also limits the extent of interaction preventing the flow of chakra between the Host and Mentor until the Host is capable of reducing the safeguards (Jounin level).  Until that time the interaction between the two is limited to the ability to reside in an “Internal World” much like A Jinchuuriki where the Host and Mentor are capable of speaking, training, and various other things.  This carries the added perk of even being accessible while the Host sleeps (though, it does reduce the effects of sleep and may not prove restful). 
This level of protection provided by the seals don't just prevent the Mentor from taking control but also locks the Host's consciousness in place and prevents other souls invading the Host's body from wrestling control from them.  It doesn't make such attempts impossible but it stacks the advantages heavily in favor of the defending Host in what would have simply been a battle of wits prior.  
As the Host progresses in skill (Jounin) and can eventually relax the safeguards enough they're able to more freely interact with their Mentor spirit.  In some cases—with the right skills-- they can even freely control the Mentor through their own Fuuinjutsu.  By this point Chakra and information travels more freely between the two to the point that they can even collaborate in a fight, share chakra, and work together to perform certain types of collaborative jutsu.  The effects of which are only directly limited by the power of the Mentor and skill of the Host. 
While the specific effects will vary from one family member to the next they all regularly make use of their fuuinjutsu in the form hidden tattoos across their body.  They've been known to store defensive markings used to stop or slow certain effects or jutsu, to store jutsu of their own for later use, or as marks for summoning.  Likewise, all of them make extensive use of tattoos that are masterfully crafted to be integrated with the markings of the seals; in some cases even creating fake seals to distract others from the real markings.  Generally speaking, the more markings they have the more talented and prepared the individual is.
In combat most clan members have relied on defensive tactics and non-lethal methods; usually to push the image of the clan being there for support and aid than anything else.  It's not uncommon to see them make use of traps, a variety of poisons, and sound based jutsu to garner the desired effect.  More rare are those skilled in the use of genjutsu but not unheard of.
==Approved by: RamenNoodlesSoup==