Board Thread:Questions and Answers/@comment-25801533-20150531094407/@comment-10587310-20150604010939

But u have to take into account that when a Quincy kills a hollow it is erased from existence and when a hollow eats a soul human or soul reaper the soul eaten can no longer be reincarnated. So it would make since that souls are being born in both the world of the living and soul society. Take the Kuchiki clan for example if they didn't have children and adopting someone into the clan is against the rules how long could the clan go on for without replenishing their numbers.