There had been an increase in Hollow sightings within the world of the living since the defeat of Yhwach. Considering the sheer amount of Shinigami casualties, the Gotei 13 were too short staffed to deal with them. That's where Quincy, like Ryuken, came in.

It was sunset by the time he made his way toward the immense source of malevolent spirit energy in the outskirts of Tokyo. As he ventured closer, a realization struck him; he could feel TWO spirit pressures, not just one... and one of them felt distinctly Quincy.

Ryuken, fearing it to be Uryu or one of his house staff, used Hirenkyaku to advance more rapidly, converging on it.

Below on the street, he did indeed see a gnarly looking Hollow... but also the strange and unfamiliar figure of a tall European-looking woman, obviously unconscious and at the Hollow's mercy. A smattering of Reishi bows laid all around. A silver Quincy pendant next to her body glinted in the suns dying rays, taunting him with all the impossibilities.

Ryuken's eyes widened exponentially. A woman... a foreign Quincy woman...