The Swooping Descent of the Dark Emissary! The Propagation of Malice

Night settles over Karakura Town as Rangiku Matsumoto tracks the whistling melody of the Arrancar she fought earlier, with Shota Toyokawa insisting on tagging along. The creature devours a fleeing Soul, boasts of its growing strength, then splits into identical copies. Toshiro Hitsugaya catches Shota from a fall, and although he and Rangiku cut down clone after clone, the duplicates keep spawning. Ikkaku Madarame and Yumichika Ayasegawa report the same swarm elsewhere. Luring the horde into a park, Hitsugaya freezes the entire mass with Hyorinmaru.

Afterward Shota finds Yui Toyokawa sitting alone on a bench, and the group carries the unconscious girl back to Orihime Inoue's apartment. Shota recounts how a truck collision killed his whole family, leaving him and Yui as Souls. Jushiro Ukitake and the researcher Akon then contact the team with their findings: every clone shares one Reiatsu signature, meaning they are a single consciousness rather than separate beings, and a concealed true Arrancar directs them to consume as many Souls as possible, its appearances always heralded by the eerie melody.

The Shinigami spread out to patrol. Yui vanishes from the apartment while the true Cloning Arrancar watches unseen from a cloud of black miasma and its clones ambush more Souls. Rangiku and Shota locate Yui at the park again, where she claims she simply wanted to return. Pressed, Shota finally confesses that after their deaths he abandoned Yui and ran, stunning Rangiku.

The Arrancar demonstrates that it can duplicate itself endlessly, complicating the hunt. Hitsugaya annihilates a large group of clones with Hyorinmaru. Shota reunites with his sister Yui and reveals their family died in a highway crash. Akon and the Research Institute determine the clones form one colony with a shared mind, steered by a hidden true Arrancar. The team disperses to patrol Karakura Town, and Shota admits he fled from Yui after their deaths.

This anime-only installment has no chapter basis and belongs to the Arrancar arc, airing as the series' one hundred twenty-ninth episode with the opening Alones and the ending Tsumasaki. A lighter Shinigami Illustrated Picture Book segment closes the episode, with Hitsugaya warning Ikkaku and Yumichika away from Orihime's baffling cooking. The story advances the anime-original Cloning Arrancar threat and deepens Shota's guilt over abandoning his sister.