Bleach Volume 60

Years before Ichigo was born, Isshin Shiba was sent to Karakura Town to investigate the presence of a hollow. Isshin would encounter the hollow, revealed to be creation of Aizen's named White, and that the creature has the same skills as a Soul reaper. The spirit pressure from the fight attracted the attention of Masaki Kurosaki, a pure-blood Quincy, as she comes to Isshin's aid. Though Masaki helps Isshin destroy White, she ended up being bitten by the hollow. The following day, confronted by Ryūken's mother over her transgression and nearly endangering the purity of the Quincy bloodline, Masaki collapses as a hole appears on her chest. Isshin learns of Masaki's condition upon returning to Karakura Town as he and Ryūken bring her to Urahara. Urahara reveals that Masaki is undergoing hollowfication and that a part of White got transmitted into Masaki's body and is consuming her soul. Though it is impossible to cure her, Urahara explains it can be treated with a vaccination made with an opposing force. However, Isshin must remain by Masaki's side in a specially made Gigai made from human souls so she can spend the way of her natural life as a human. Knowing he must relinquish being a Soul Reaper and remain trapped in the Gigai, Isshin abruptly accepts. Isshin concludes the story by revealing to Ichigo that he regained his Soul Reaper powers the day Masaki died. Isshin then explains that Masaki's death, along with Uryū's mother Kanae Katagiri, was caused by the propagator of the Quincies: Yhwach. Later, Ichigo is taken back to the Royal Palace under goes a new test where he chooses his own Asauchi that would be forged a new Zanpakutō. As Nimaiya begins to forge, it is revealed that the entity known as "Hollow Ichigo" is both an offshoot of White and the real Zangetsu. Furthermore and the spirit known as "Old Man Zangetsu", reminiscent of a younger Yhwach, is actually the personification of Ichigo's Quincy powers. Meanwhile, as the Soul Reapers prepare for another assault by the Wandenreich, Yhwach welcomes Uryū to their side.

Everything But The Rain
Contains chapters 531 - 540.