Pneuma Release: Soul Conjunction

An extremely powerful and fatal technique. It was deemed a kinjutsu due to the effect. It can only be activated when the user is dying, as that is when the soul leaves the body. The user conjoins both his and the opponents souls together, mixing his with the enemy. When his soul is conjoined, the opponent starts to slowly die, as the users soul starts to eat away and the body. The opponent will die within 1 week, a slow and painful death.

It is unnavoidable and unstoppable. Even if the opponent is invisible or invincible.