Renji Abarai

Abarai and his captain, Byakuya Kuchiki, are sent to the human world to find Rukia Kuchiki and bring her back to Soul Society. Once they find Rukia and prepare to return home, Ichigo Kurosaki arrives to save Rukia. Renji and Ichigo briefly fight; however, Ichigo easily gains the upper hand after a sudden release of reiatsu, which was actually random bursts of resolve. Byakuya steps in and easily defeats Ichigo. After they return to Soul Society and Rukia is imprisoned, Renji periodically checks up on her, trying to keep her spirits high despite her impending execution. It is revealed that Renji is a childhood friend of Rukia's; their relationship was strained by Rukia's adoption into the Kuchiki family and Renji had striven to prove himself as a shinigami in order to match Rukia's new social standing and to be acknowledged by Rukia's adoptive brother, Byakuya.

Ichigo soon arrives in Soul Society to continue his attempted rescue of Rukia. Renji, feeling Ichigo is to blame for Rukia's sentence, goes to fight him. Despite his best efforts, Renji is defeated and subsequently imprisoned for his failure. Before Ichigo leaves, Renji pleads for Ichigo to save Rukia. Once he recovers, Renji escapes from his confinement and begins training to achieve bankai of his zanpakutō. After completing his training, Renji sets out to free Rukia. Before he can do so, however, he is stopped by Byakuya. The two clash with their respective bankai. Byakuya's mastery of bankai and Renji's inexperience result in Byakuya's victory.

Following this battle, Renji goes to the site of Rukia's execution in a last attempt to save her despite his extensive injuries. Ichigo, having beaten him there, entrusts Rukia's safety to Renji and the two try to escape. Along the way they are met by Kaname Tōsen, who teleports them back to the execution site. Upon learning that Tōsen and Sōsuke Aizen are traitors that intend to kill Rukia, Renji fights to defend her, but is effortlessly defeated by Aizen. Rukia is ultimately saved by Byakuya, though Aizen is able to escape the Soul Society.

As Aizen's arrancars begin to threaten the human world, Renji is one of a group of Soul Reapers sent to help defend against the arrancar attacks. During the second arrancar invasion, Renji fights against Ilfort Grantz, whom he is able to defeat once his power limit is lifted. After the battle, Renji is recruited by Kisuke Urahara to help train Yasutora Sado. Upon Orihime Inoue's capture by the arrancar, however, Renji and the other Soul Reapers are recalled to Soul Society.

Unwilling to abandon Orihime, Renji and Rukia go to Hueco Mundo to join Ichigo, Sado (Chad), and Uryū Ishida in their attempt to rescue her. After their group splits up, Renji is joined by Dondochakka Bilstin while traveling through the arrancar base Las Noches. They eventually encounter the Octava Espada, Szayel Aporro Grantz. Upon being drawn into battle with the Espada, Renji discovers that Szayelaporro has nullified all of his abilities as a result of Szayelaporro's earlier research. Uryū soon arrives to lend assistance, though his attacks are also rendered inert by Szayelaporro. No longer able to attack, Renji and Uryū are left at Szayelaporro's mercy until Mayuri Kurotsuchi arrives to save and heal them. He, Rukia, and Chad, are then attacked by a furious Yammy, who is revealed as the strongest of the espada, going from 10 to 0.

Seventeen months after Aizen's defeat, Renji heads to Karakura with many other high level shinigami, observing the restoration of Ichigo shinigami abilities and his battle with Kugo Ginjo. Renji then engages the Fullbringer Jackie Tristan in combat, and easily defeats her, revealing that he had trained over the last 17 months to be powerful enough to fight Aizen.

After attending Sasakibe's funeral with Byakuya, the two face off against Stern Ritter F, Äs Nödt, after the Wandenreich invade the Soul Society. Byakuya's bankai is stolen and is used by Äs Nödt which almost kills him. Renji attempts to avenge Byakuya by activating his own bankai, but is blindsided by a kick from another Stern Ritter and is knocked across the Seireitei. After the invasion, Shinji Hirako heals both Renji and Rukia and are taken along with Ichigo and a still-breathing Byakuya to the Royal Palace by the Royal Guard. Upon being healed by Tenjiro Kirinji's healing techniques, Renji regains consciousness and accompanies Ichigo (and Kon) to the next palace.

After finishing his training with the Royal Guard (and perfecting his Bankai), Renji and Rukia return to Soul Society and arrive just after Sternritter "S", Mask de Masculine, has defeated several Captains and Lieutenants in a battle. Renji fights him and eventually kills him by using his perfected Bankai for the first time.

The epilogue of the series reveals that ten years after Yhwach's defeat, Renji has a daughter with Rukia named Ichika.