Shunsui, the laid-back and flamboyant Shinigami, was sitting on a rooftop, sipping his sake & enjoying the view of the Soul Society. Suddenly, he felt a disturbance in the air and looked around with curiosity.

“Hello there. I am Shunsui Kyoraku, the captain of the 8th Division. His demeanor changes.

“Oh… an enemy? How unfortunate. I’d rather not do this but Old Man Yama will be mad if I don’t dispatch you. Let’s skip the games, shall we?” Shunsui’s cheerful flamboyant personality is no longer there. He’s kind of serious now…

Bankai: Katen Kyōkotsu: Karamatsu Shinjū (花天狂骨枯松心中, Bones of Heavenly Blooming Madness: Withering Pine Lovers'Suicide; Viz "Flower Crazed Heaven Bone Spirit Withered Pine LoveSuicide"): Shunsui considers his Bankai a last resort that he will only use if his allies are far enough away, lest they be caught up in its effects. To release, Shunsui holds his Shikai out in front of him with the blades pointing down, which prompts several black tendrils to extend out from him like shadows (resembling ink-drawn pine branches) while his Zanpakutō Spirit, Katen, manifests behind him. A vast area around Shunsui is subsequently overcast with an aura that alters the perception of those it reaches, making their surroundings appear "gloomy, desolate, and full of despair" as they feel chills, and making the sky look as if covered in eerie yellow squares, like the paneling of a theater stage. The blades of Katen Kyōkotsu remain in the shape of their Shikai form.

Bankai Special Ability: Shunsui's Bankai forces him and his opponent to act out the roles of a tragic play, based on the story of a doublesuicide of two lovers. Each of the Bankai's four techniques represents an Act in the overarching narrative — conveyed by Shunsui reciting a brief exposition poem — and casts an unavoidable, curse-like effect upon Shunsui's opponent; the final Act is meant to assure the opponent's death by destroying their head, meaning that only one who can survive losing their head can survive the Bankai.

Ichidanme (Act One): Tameraikizu no Wakachiai (一段目　躊躇疵分合, First Act: Hesitance and Apportionment of Wounds): Shunsui activates this ability and immediately all his wounds appear on his opponent's body, bypassing even intangibility, with any and all wounds being shared and further, being unable to outright kill from the mutual wound sharing. Any wounds that Shunsui or his opponent inflict on each other will emerge on their body. Shunsui compares this to the story of a man who suffers from the same wounds as his partner, yet cannot die from them.

Nidanme (Act Two): Zanki no Shitone (二段目　慚愧の褥, Second Act: The Pillow of Shame): Black spots appear all over the body of Shunsui's opponent, causing them to bleed profusely and without end. Continuing his story, Shunsui likens this to the man feeling shame after wounding his partner, causing him to collapse in shame and become incurably ill.

Sandanme (Act Three): Dangyo no Fuchi (三段目　断魚淵, Third Act: The Severing Abyss): Shunsui summons an immense watery prison that encapsulates himself and his opponent and slowly drains their Reiryoku whilst freezing them both in the water until one runs out of Reiryoku and dies. This watery hell is literally inescapable and seemingly reverts direction upon attempting to be fled somehow, as well as forcibly begins to freeze one's resolve as well as their body. Shunsui and his opponent are engulfed in a massive, inescapable body of water, which both are meant to remain in until one of them runs out of Reiatsu and drowns.

Shime no Dan (Final Act): Itokiribasami Chizome no Nodobue (〆の段　糸切鋏血染喉, Final Act: Thread-Cutting Scissors upon a Blood-Streaked Throat): After sheathing his swords, Shunsui winds a white thread around his opponent's throat multiple times before pulling it taut, leaving a deep cut in their throat that expands before blowing up their head. Completing his story, he likens this to the regretful man's partner ignoring his pleas and mercilessly shearing his throat.