This wasn't going to end well.

Watching the scene unfolding above her, Hinamori knew their attempts were futile. With each felled shinigami, their chances of victory slimmed. Conversely, the loss of the espada didn't even cause Aizen to flinch. They were just tools, another distraction. That was evident when he himself killed Hallibel, the last espada remaining. Aizen needed no one, only himself.

She turned her head slightly, glancing at Matsumoto. Kira seemed to have done a good job healing her, though her wounds were still serious. Nevertheless, she was sure Matsumoto would survive. As that thought crossed her mind, Hinamori looked away. She couldn't say the same for herself. This was one battle Hinamori Momo would pour her heart and soul into. She didn't intend to live. That was never the plan.

Ever since waking up from her comatose state, she'd heard whispers of the oncoming war. It was inevitable, the shinigami said. The highest ranking officers would be sent to the front lines. There would be no pointless sacrifices. For a long time, Hinamori tried to ignore those whispers. Part of her hoped that they would not be victorious against Aizen, that there was some chance, no matter how slim, that things could return to how they had been previously. She had spent countless hours fantasising about this, until the reality hit her. The highest ranking officers would be sent to the front lines. That included Hitsugaya Toushiro. In that moment of clear realisation, all Aizen's illusions were lifted from her. Not only the ones placed there by the hypnosis of his zanpakuto, but the ones he had woven so carefully himself. The thick web of lies Hinamori had been trapped in for so long, torn between those she loved. From that moment, Hinamori began to formulate a plan. She knew the chances of success were low enough as it was. This plan was all or nothing. She drew her zanpakuto and arrived on the battlefield fully prepared. Such injuries to herself and Matsumoto hadn't been part of the plan. She panicked inside, but retained a calm demeanour. A few moments to calm herself and surely she could improvise. She waited for the opportunity to present itself.

She watched, helpless, as the man she had loved, her former captain, and the man she now loved, her childhood friend, clashed in the air. No, she thought, no. This wasn't according to plan, not in the least. Hitsugaya wouldn't be able to defeat Aizen. At least, not yet. She lay there, her breathing shallow, the pool of dread inside her growing greater with every passing minute. Perhaps she wasn't going to be able to save him. She closed her eyes, allowing the despair to consume her.

That was when she heard his voice in her ear.
"Momo"
Her eyes shot open. He still took her breath away. She gazed up at him with awe. She didn't even need to fake it. The part of her that felt this had never died, it would always be something she felt towards him. It made her her. Her devotion to him was just another trait of her personality. One which he knew all too well. Her heart stopped beating momentarily when he placed his hand on her shoulder and bends down so their eyes are level. He was her captain once again. His eyes were kind and warm, framed by wide-rimmed glasses which gave him an air of intelligence.
"Captain" She breathed, without even thinking. The words came to her naturally, as they always had. He smiled at that.
"Yes, Momo. It's me"
Tears welled up in her eyes, but she refused to let them fall.
"Captain Aizen... You've come back"
He nodded, and it almost seemed sincere.
"Momo, there's something I need you to do for me"
Of course she was expecting that. She only existed to be used by him for whatever purpose he saw fit. That was why she was his vice-captain. She would have made a good subordinate to him if she'd only been stronger. No matter though, he would still make use of her. And she would be more than willing to do his bidding. Just like his dog.
"Anything"
A grin spread across his face. Hinamori's mouth formed a small smile.

There was no feeling in her body. It was as if her nervous system had been completely shut down. There was nothing but numb. The smile remained on her face as Hitsugaya approached, sword outstretched. She spread her arms wide as the blade approached her chest. She wanted to embrace him one last time. She felt cold as the sharp steel pierced her body, but no pain. He had vanished from her sight, but she could feel him behind her. Her heart fell. She would not have him in her arms again before she died. Dismayed, she raised a hand to Hyorinamru.
You did it, Shiro-chan, she thought. Her smile faded as a trickle of blood ran from her mouth. Distantly, she heard Histugaya cry out. The pain of the cry stung her. He took her into his arms and she could read the question burning in his eyes.
Why?
"Shiro-chan...," It hurt to talk "Why...?"
Her words mirrored his thoughts. He didn't understand. Why was he killing her? No, she wasn't asking him that. Her breath caught in her throat. The blood stopped her breathing properly. She couldn't even offer him an explanation.

Why, Shiro-chan? Isn't it obvious why? I'm always holding you back. You want to protect me, but you should be protecting yourself. As long as I'm around, you can't defeat Aizen. With me dead... You can kill him. My death is the perfect catalyst.

Perhaps he would figure it out on his own one day, after the war. Of course he would, no one else knew her better than her Shiro-chan. It would be wrong for her to doubt him in her final thoughts.