Kyashi Urami is the container of the demon spirit Kyosuke. When she taps into his chakra, it increases every physical aspect of her body: Near-limitless chakra, massive strength, increased speed and stamina, and increased healing. Kyashi has access to Kyosuke's chakra due to an incident that occured when Kyosuke tried to control Kyashi's body. Kyashi was able to push him back with pure willpower, however, and Kyashi, impressed, allowed her to access his chakra reserves, although he forces his chakra on her when her life is in danger.
By simply tapping into Kyosuke's chakra, Kyashi's blue eyes turn red, her pupils become slitted, and her nails and canine teeth grow long and sharp. Kyashi first unlocked this stage when almost killed by Rain bandits at the Fire Temple. Depending on how much chakra is unleashed, the crimson chakra could glow around her body in an untamed way.
Even though this is the weakest state of her transformations, it is still a force to be reckoned with. Stronger than Naruto's Jinchüriki form, this heightens the senses of sight and hearing, quickens her body's healing of wounds, and increases her speed to such high levels that nothing short of a fully mature Kagirinaigan can track her movements.
During the attack on the latest Akatsuki base , when Kyashi was at the mercy of Ryun, Ryuka, and Otonami, Kyosuke comes to her aid, giving her some of his chakra. The amount of chakra is so great that it leaks out of his body in a denser state. All the physical traits of the basic Jinchūriki form are present and slightly altered, including black rings around the eyes, longer nails and canines, and more berserk looking eyes. This form also comes with an additional bonus; the red chakra becomes a complete shield around her body, in the shape of a wolf, complete with long ears and a tail, known as the demon wolf's cloak or shroud.
In his one-tailed transformation, Kyashi fights more like a beast. Instead of using her fists, she uses her sharpened claws. In this form Kyashi has also shown the ability like in her other forms to make a shockwave with a simple wave of an arm. While she can stand on her own two feet, she can move at greater speeds on all fours. Her most powerful weapon is the chakra itself. The bubbling chakra appears to have a mind of its own: when a strike that was meant for Ryun missed, the chakra itself stretched off Kyashi's arm and hit Ryun before he could react. Since the chakra is sentient, it is extremely difficult (if not impossible) to predict Kyashi's movements. Ryun and Ryuka were able to see Kyashi perfectly, but couldn't predict what the chakra's actions with their Sharingan. The chakra can also stretch far from the body, as when Kyashi was shown using her "arms" to attack from great distances. At one point she was on the opposite side of the forest and still attacking the three with her chakra arms. The shield around her body appears to be impenetrable, comparable to Gaara's Ultimate Absolute Defense: Shield of Shukaku.
However, despite not being able to be read with the Sharingan, the Kagirinaigan makes up for it.
In this form, Kyashi's physical characteristics match the first two forms, but her red eyes and canines grow larger, and her lips get a black outline, similar to wolf gums. The chakra shield's only difference between the one-tailed transformation and the two-tailed is the extra chakra tail that has grown.
While in this state, Kyashi is still in control of her body, though to what extent is unknown.
After Sachi revealed herself to Kyashi and taunted her, Kyashi went into a rage, attacking Sachi in the one-tailed state. When it was clear that didn't work, Kyashi's fury increased, and she skipped right into the three-tailed transformation.
The amount of chakra produced from this form is devastating. The very air around Kyashi begins to hurt. This is the strongest form Kyashi can reach and control. With the standard chakra shield's protection and attack power, a simple roar has the power to create a devastating sphere of destruction.
However, in this form, Kyosuke can also force control over her, due to him being closer to her mind while in this state. Such was shown when he took control and fought with Seireitou Hyuga, who had transformed himself into Kuruk Uchiha.
To combat Kuruk's spirit-bending, Kyosuke pushed Kyashi's body to the Four-Tailed form. Kyosuke's demon chakra began to morph Kyashi's body slowly, covering her mutating state with chakra. Everything on her whole body became completely solid, her eyes becoming empty glowing circles surrounded by a black mask of chakra.
In this state, in effect, Kyashi takes the place of Kyosuke within her consciousness. Kyosuke has complete control over Kyashi's body, making it a mere skeleton for his chakra, and every living thing in its way a target. The four-tailed transformation has all the benefits of the other tails, with upgrades. With a simple wave of his hand, he can send a shock wave of destruction for miles. The chakra shield, while being solid, still completely protects Kyashi's body, and is so hot that it can burn the skin on contact. If Kyashi is hit, the chakra itself can form another body, and strike back almost instantly. Kyosuke also has the ability to charge a concentrated ball of chakra, consume it, and then fire it with such a force that it could destroy three Rashomon gates without losing strength. Finally his chakra shield's defensive power is so great that it is impregnable to any form of attack. Even Kuruk's powerful attacks could not break through it.
In the end, despite it being Kyashi's strongest Jinchūriki form revealed so far, the four-tailed transformation is Kyashi's greatest downfall. Due to the fact that Kyosuke has complete control, Kyashi is at his mercy, easily able to be put under the option to be sealed away forever, although he has never done that, returning her to her normal state when he is done. Also, due to the constant destroying and regenerating of cells, Kyashi's life-span is shortened.