BLEACH: The Dusk In Red

Yamada thrusted her Zanpakutō down into the ground before shouting,

"BANKAI!"

behind Yamada, a giant red and velvet throne, decorated in gold engravings erupted from the ground. When she sat on it, her spiritual pressure began to increase exponentially, while the air surrounding the two began to change.

Omega ran up to her to try and attack once again, but a strange barrier stopped him from doing so.

"My Shikai is actually a wind type Zanpakutō. It can condense all the air and wind within five meters of myself, but once I do, I can fire it outside of this radius. My Bankai on the other hand, can increase this range up to the entire area of Soul Society!"

Omega raised his guard, expecting an attack from every direction however what came next was something he could not guard against. 

The surface of his skin began to freeze as he felt a strange sensation inside his body. His insides were boiling, or rather it was his blood. His senses had finally caught up to his body when he realized that he couldn't even breathe, and then his coughed up a mountain of blood as his lung s exploded.

He quickly undid the effects on his body, returning him back to normal, but not even 2 seconds later, the damage continued.

"Ryōtō Mikoto: Tenkū no shirei-kan! I turned this entire floor aside from the area around me into a vacuum, mimicking the depths of space. As air is sucked out of your body, your insides will expand, your body will freeze, and your blood will boil. Even if you reverse the effects with your causality control, you will still be inside the vacuum and it won't take long for your body to feel its full effects."

She looked over to the side, and saw Tachibana who was grovelling on the floor in pain. Half his body was already frozen, and he was drowning in a pool of his own blood.

He might even be dead already.

Omega tried reversing the effects one last time, before quickly making his way towards Yamada. He raised his sword above his head, as he was about to perform a heavy vertical slash.

She simply pointed at him as another invisible slash sped towards him. He easily deflected it, but then several spears of condensed air suddenly spawned around his stomach, before piercing it.

Thanks to the vacuum, blood spilled out even more than it should've, but then it started to freeze afterwards.

Omega was about to erase the effects of the vacuum once again, but once he noticed Tachibana's dead body, he just gave up. He fell to the ground as exhaustion overtook him, all while Yamada just looked at him pitifully.

"How sad. You only look like a child yet you had so much potential."

She was sure of it. That boy could most certainty keep fighting for at least another 3 days if he wanted to. But he appeared to have given up. As they fought this entire time, Yamada could see in his eyes that he didn't fight for himself, his only purpose was Tachibana. But now that he was dead, the boy had nothing left. It was because of this, she showed one final act of mercy. 

She returned oxygen back to Omega. Even if he could breathe now, too much damage had been caused. Aside from his own ability, only Kaido at the level of Tenjiro could save him.

"People your age shouldn't have to worry if they will survive the next battle. Come back with me, and I can show you the world which Tachibana could never offer you."

Omega just looked at Yamada before mouthing something. She couldn't hear what he said, but it wasn't that he didn't say anything. Yamada was sure he said something, but whatever it was, it felt blurred out.

"Ah, such a shame."

She removed the oxygen from him one last time, before killing him once and for all.

She closed her eyes as she relaxed on that throne. Although she won, she felt tremendously exhausted. Killing all the Vasto Lordes from here wouldn't be too hard of a task for her, but the further the target the poorer control she had on her Bankai. If she turned the area around them into a Vacuum, the hollows would die, but so would any Shinigami/soul that gets caught up in it.

Because of this, she didn't like to use her Bankai.

The next time she opened her eyes however, she found herself in a strange dream.

She was standing before Omega much like before, with the boy himself being fully healed. Her Zanpakutō was sealed, and Tachibana was alive and well. As their fight started again, it would continue much like before.

Yamada released her Shikai, which Omega would quickly adapt to and counter with his causality controlling ability. As the fight grew too close, Yamada would try to release her Bankai. But before she could, the flow of the battle completely changed.

She was about to thrust her sword into the concrete, but before she could call out it's name, Omega flash stepped in front of her as he said.

"Getsuga Tenshō."

A burst of blue Reiatsu exploded out of his Zanpakutō which raged violently. As it did, it took a unique shape, similar to the blades of saw, spinning to cut down a tree.

Yamada quickly raised her blade up to defend form it, and the clash caused sparks of flickering light to jump out in between the two. She tried to hold on, but a crack began to form in her Zanpakutō as it eventually broke in two.

Yamada tried to move back, but Omega was quicker as he slashed her across the chest. A river of blood poured out from her wounds as she fell to her back.

The pain, it was far too real for it to be a dream. This was reality.

"What did you do?"

As she coughed up some blood, that was when she realized that Omega had released his Zanpakutō. But at what point did he do it? She never heard him say its release command.

"It was back then wasn't it? That thing you said which I couldn't hear. That was when you released your Zanpakutō? Was hiding its release command intentional?"

Tachibana applauded as he approached the dying Yamada.

"That which has no name, has no power. That isn't completely true. There are two things in this world which that rule doesn't apply to. One of them would be Omegas Zanpakutō. If you rip away the name from an object, it would loose its power and meaning, this is especially true for Zanpakutō whose names are tied to their very existences. However, Omega's Zanpakutō is the only exception. It ended up this way on purpose of course. I made his Asauchi with the deaths of squad 0 in mind."

Omega's blade is the one that shall slit the necks of Squad 0. That much was certain. Unless you were Yhwach who could forcefully take his powers back, anyone else would have trouble against the monk of names. But what could Omega's Zanpakutō's who existed outside of those rules do?

"You still have two questions left. Do you feel like answering them now?"

With the last of her strength, she raised her hand before showing him her middle finger.

"Can you fuck off already?"

Tachibana just sighed in disappointment as he ordered Omega to finish her off. Just before she died though, she had a vision of a group of certain students.

"Those three... they will shine brightly."

With single swing of his Zanpakutō, Yamada's head was severed from her body, marking her death.