Part I
Incoherence
He began to notice something was wrong fairly quickly. Somewhere in between glances and small movements out of the corner of his eye he observed something of a specter coming from her, a dark shadow that he couldn't quite describe.
Surely Minato was imagining it though. And with the passing time he would brush her off, brush it off. She was a kind girl after all, she'd never do anything to harm anyone or anything, or at least he liked to think such a comforting reassurance. In reality, Yamagishi was a very peculiar girl. Petite and introverted, curious and observant; she was a meticulous and careful intelligence that often had a motherly aura to her, carefully looking out for everyone in their group of friends. Hanging behind on their missions and whispering into his ear during their travels, she was something of an anchor that always promised a safe return. Everyone loved her, everyone respected her—yet he couldn't shake it, he couldn't shake the eerie shiver that went down his spine when they made eye contact, when they would sit alone for those brief moments in the living room of their dorm. Her eyes were a deep grey with a peculiar tint of green, almost alien like in those moments of dimmed light during the night hours; he could feel them looking at him from across the room, going through him, taking something away from him.
Perhaps it was all in his head, perhaps he was over-analyzing everything. Still, her blank and almost lifeless stares and her silent murmuring to herself he thought he caught now and then continued to unsettle him, to remind him that something wasn't quite right with their rather gentle friend. He couldn't see her being unstable or violent, but the tension she hung around herself was unmistakable. Even stranger, no one seemed to notice, no one seemed to care. They were all warm to her, seemingly unaware of her bizarrely sinister aura, or what seemed to emanate off of her.
She didn't intend to give off these feelings. On the contrary actually, she wanted to stay under the radar. Being as reserved as she was, she preferred to stay subtle, unnoticed, unseen. She was glad her friends and roommates trusted her and enjoyed her presence; in truth she could hardly say the same about all of them.
As an introvert, she had mastered the art of keeping things inside. With recent traumatic events, she felt something different. After being left in that otherworldly darkness, she'd been losing sleep for weeks. Nightmares of that shadowy dimension and the nightmarish creatures and entities that her roommates had saved her from kept her up continuously. People had left her there in the first place though, her peers had stranded her on that surreal and dark plane. She tried to forgive them, and in some sense she did—deep down it still festered though: trusting others, giving her confidence in her allies; she could feel an intensely burning anger now and again, silently flaring in those random instances throughout the day.
Moreso than that, that peculiar boy, Minato—she couldn't quite understand her fixation on him. It was innocent enough at first; he was among the first she saw in the dark realm, and it was him who seemed to draw her out of the darkness altogether. Now she would sit in silence, watching him think, breathe, be. Even when the group was together she could easily tune out everyone else's interference, as if they needn't exist.
He was special though.
She found it somewhat irritating, to think that someone could be so ubiquitously present in one's mind. At first she thought it may have been a simple crush, a simple affectionate desire—as time passed though, as the season wore on and fall drew near, she began to wonder if it was something different, something obsessive, something off.
Worse, she found the mysterious draw he had to other people to be infuriating. They didn't notice though, they'd never notice when she'd grit her teeth, when she bide her anger, blankly and silently letting others, namely obnoxious females, flaunt themselves at him. She would meticulously plan out how to approach him, how to speak to him, how to hold herself around him. This was simply how it worked, how her psychology seemed to approach him. He was far above most of these people, even if he didn't know it. So she would wait for him to come to his senses—wait for him to see that she was clearly the optimal choice, the optimal companion. They were all so unaware of her feelings, of her intentions; all caught up in their own lives, in their mission to push back the dark. In some sense this worked in her favor, in some sense this let her inch closer and closer to him. Every mission she'd watch him, astrally looming over him, listening to every word he said, his every breath even. She couldn't shake the bitterness, the anger towards everyone else.
She wanted to take him away from them. She wanted him to see them all for what they were: people who couldn't be trusted. None of them could be trusted after all—Fuuka knew this first hand. Her friends and peers slowly began dissipating into the shade, becoming forms she wanted to stray from, becoming things she couldn't quite grasp. She wanted to love them but she couldn't, only he deserved it. Measures needed to be taken to secure the finality.
He was the only one who seemed to even be solid anymore, and it was that very reason that led her to do what she did.