Talk:Potential Creation/@comment-2197197-20131211032302/@comment-4867780-20131213002224

It comes back to the time before Rukia was forcefully brought bak to soul society. She unknowingly had the Hogyoku hidden within her soul some times ago (courtesy of Aizen's schemes), and during the time she spent hanging around with everyone it seeded Sado and Orihime with what would later mature into full-fledged abilities. So no hollow nor fullbring involved, as far as I know.