Rukia and Kaien, the Sorrowful Reunion

Rukia converses with Aaroniero, and realizes that he is the real Kaien, who states that after he was killed, he was resurrected in Hueco Mundo, where he became one of Aizen's Espadas. Kaien offers Rukia a chance to atone for killing him by allowing him to kill her, and Rukia accepts, with the caveat that she will be allowed to rescue Orihime Inoue. Kaien reveals that he was joking, and instead, instructs her to kill all of her friends. Realizing that he is an imposter, Rukia begins to fight Kaien, and Kaien quickly gains the upper hand, as he was the one who taught Rukia how to fight.