Bleach belongs to Tite Kubo, which is not me.
May be small spoilers, but if you actually knew Sasakibe died, you are probably past them anyways.
Apathy
After his many, many years of life, Yamamoto had begun to assume that nothing else could faze him. He was wrong.
Baby
Sasakibe had sworn his life to Yamamoto and never swayed from that path. Yamamoto wonders if the man had never desired a family or if he had simply put that desire aside.
Chuckle
Was it wrong that Yamamoto had remembered a few of the better moments rather than mourn his lieutenant's memory?
Dead
It was such a foreign concept. So simple, yet ultimate in its illusive path.
Excitement
Yamamoto would not deny the fact that the thought of ripping the Vandenreich to shreds brought a savage grin to his face.
Fear
He had watched Sasakibe get cut down before, injured, in fourth division, et cetera. Yet every time there was the smallest thought that something could happen. This time it was justified.
Guilt
He had felt Sasakibe battling. He had felt the battle, known that something major was happening for bankai to be released. Why didn't he go investigate?
Hot Spring
Even the scalding, relaxing waters did nothing to sooth the raging tempest within Yamamoto.
Insubordination
Releasing a zanpakutō in the Seireitei was a crime. Not serious, perhaps, but a crime nonetheless. Sasakibe didn't hesitate to commit it in an attempt for the greatest good. Yamamoto was unsure of how he felt about that.
Jump
Yamamoto wondered if the battle was truly justified. If Sasakibe had just stood down as he was wont to do, would he still be here?
Kill
Yamamoto was used to death. Soul Reapers died daily in the line of battle. This was not natural in any sense of the word. Sasakibe was killed, with no motive beyond making a statement to the Soul Reapers.
Loyalty
And yet, the Quincy were only following the orders of him.
Morals
Yamamoto knew that desiring to destroy the Quincy kingdom is far below any sense of morals a good Soul Reaper should have; but he just didn't care.
Near
It was nearly heartbreaking—in the greatest sense of the word that Yamamoto could feel, at least—to known that Sasakibe had died and Yamamoto did not do a thing to help him.
Oxymoron
The boiling ice of emotions surged through Yamamoto's veins: fear, guilt, desire, excitement, laughter—some appropriate, some not so much.
Party
Some Soul Reapers celebrated the death of their comrades, saying that their achievements in life far overshadowed the setback of death. Yamamoto couldn't bring himself to agree.
Quick
They struck quickly. They showed up, made an impression, and said what they needed to. Their unfaltering efficiency was almost to be admired.
Respect
It was only after his death that Yamamoto began to truly appreciate Sasakibe's actions around the division.
Strange
No matter how much Yamamoto had tried to say that the attack on Sasakibe was irrational, he could not deny that they had done so simply to rile him up. And oh boy, did it work.
Tower
Yamamoto was the immovable pillar of the Seireitei. Now, however, it seemed as though he may crumble under his own weight.
Upside down
That was how Shunsui had described the situation. 'All topsy turvy and flipped around.' Yamamoto understood that it was merely an attempt—as ill-timed as it was—to lighten the situation. But the comment hurt so badly.
Vulture
Now it was time for Yamamoto to finish what Sasakibe had started.
Weep
Say what you will about Yamamoto's emotions regarded the funeral, but it would not be stated that he wept. No matter how heartless that made him sound.
X
As Yamamoto reflects on the strange language written on various papers about Sasakibe's desk, he realizes that maybe, just maybe, he really should have paid more attention.
Yearn
Of all the emotions that were stated previously, only one came to the forefront of Yamamoto's mind. Revenge.
Zanpakutō
Deep within his soul, burning with, and as bright as, Ryūjin Jakka, one thought formed with that one emotion. As far as either of them cared, Sasakibe's murderer was already dead.