Orihime Inoue
When Ichigo and his allies entered the Soul Society, Mayuri aided in the search for the Ryoka and found Orihime Inoue and Uryū. Orihime escaped and Mayuri reluctantly fights Uryū, seeing no need to study Quincies any further. Uryu is initially too weak to fight Mayuri until the Soul Reaper revealed that he experimented on Soken Ishida which his opponent unlocking his full Quincy powers prior to escaping. Mayuri remained on the sidelines for the duration of the search out of disinterest, even after he learns of Sosuke Aizen's betrayal.