After an awe-inspiring battle with Ichibei Hyousube—leader of the Soul Society's Royal Guard—the powerful Yhwach moves into the final stage of his master plan. He aims to slay the Soul King, the being whose very existence maintains the status quo of three worlds: Hueco Mundo, the Soul Society, and the realm of humans that Ichigo Kurosaki and his closest friends hail from. Conquering his own bout with the remainder of the Royal Guard, Uryuu Ishida joins Yhwach in his efforts to create a new world in his image. With a flood of resolution and newfound power, Ichigo rushes to stop Yhwach from accomplishing his ultimate goal and save the countless lives within the three existing realms. But Ichigo has a complicated lineage, one that leaves him susceptible to Yhwach's sinister influence. Meanwhile, in a final desperate gambit, Jirou Sakuranosuke Shunsui Kyouraku, the newly promoted head captain of the Soul Society's combat corps, enlists the help of an old enemy whose immense power may turn the tide of battle.

On her 16th birthday, Himari Momochi receives a letter stating she has inherited a mansion called the "Momochi House." Having been raised in an orphanage, this mansion is the only thing left of her real family, so Himari pays no mind to the rumors that it may be haunted. Upon entering it, she meets Aoi Nanamori and his companions, Ise and Yukari, who all seem to be squatting in her new home. Although they warn her to leave the house, Himari vows to be the one to make them leave instead. But soon, she is attacked by youkai and finds out that the house sits in the space between the world of the living and the spirit realm. Even more surprising, Aoi was chosen to be the guardian of the house—a position originally meant for Himari. But this great power came with an awful price: Aoi can never leave the mansion, and his existence in the human world has been erased. Ignoring his pleas for her to leave the mansion, Himari promises to help Aoi break the housebound curse as she begins living under the same roof as him.

The player Dongdong mistakenly entered the game world "Azure" and changed into the skeleton, the weakest wild creature. The unidentified Dongdong used his years of gaming experience to amass a band of wild monsters early on. He met the main character Bubble, made a deal with her to become her strongest pet, and then set off on an amusing and thrilling adventure with Bubble and his new pals in "Azure." The phenomenon of NPCs and wild monsters in the game gradually awakening and yearning for the human world was also identified at this time by Dongdong. To learn the truth and get back to your regular life. The main character group, lead by Dongdong, as well as awakened NPCs, regular players, game developers, and other entities started to debate how the two worlds were connected.