From the very start, one of Bleach's best friendships was between protagonist Ichigo Kurosaki and his Soul Reaper friend, Rukia Kuchiki. They hunted Hollows together in the earliest arc, then Ichigo stormed the Soul Society to rescue Rukia from twisted justice. They fought together to rescue Orihime Inoue from Las Noches, but after that, the two of them began to go their separate ways. It was sad to see for many Bleach fans, but it was also critical for Ichigo's and Rukia's respective character arcs.
Source：https://www.cbr.com/ichigo-rukia-bleach-tybw-arc/
