Warnings: slash, character death.
Although the circumstances of Shisui's death were revealed relatively early in the manga, I've used some plot points from around chapter 398 somewhere. It's not a particularly blatant spoiler, but just in case.
Disclaimer: Naruto belongs to Kishimoto.
Also, I've not been trolling around in the Naruto fandom for quite some time so if there are some similarities to someone else's story, I apologize.
The moon is high and bright in the midnight sky, its reflection shimmering and flittering as it dances playfully along the black surface of the river. It flickers and distorts across the water, shifting with the currents; playful, enticing him to join it in its game.
His dark eyes move to the slender form of his friend, and he watches him wade waist-deep into the cold water, his kimono pooling around the delicate swell of the hips that Itachi has seen naked many times before. Shisui's pale fingers flutter around in the moonlight as he runs them through the wavering form of the moon in the water. The image dissolves into tiny flecks of glimmering light that dance like little pixies around his delicate fingertips, and he laughs very much like the child he used to be – like the children they both used to be.
They are children no longer, and Itachi knows this first hand – has known this since the very first time his kunai tasted the blood of another living, breathing human being; since he heard his very first victim's scream of terror choke off into a pitiful and helpless death gurgle as his blade severed their vocal chords in a warm gush of blood. He felt that innocence leave him tangibly, like the blood that splashed crimson against his pale face. They are shinobi, he knows, and they can't afford to be children. Not for tonight; not even for one last time.
And Itachi wishes now more than ever that they could still afford to have that innocence.
But there is no more time for that, not now, not anymore, and he wades out to where Shisui is standing, moonlight cascading down his back. Shisui turns his head and looks back at him, hearing his approach. Their eyes meet, and there is a moment where they just look at each other, not speaking, not needing to, before Itachi steps close to him and reaches out to him with his long and pale fingers.
Shisui trembles under Itachi's frozen touch, as his hands gently grasp his face, tenderly, as if his face is a fragile and treasured object – and to Itachi, it is. Shisui is not beautiful, not in the way Itachi is. He is tall and gangly, with hopelessly long limbs that would get tangled if he was any less of a ninja, and his close-cropped hair sticks out awkwardly at the strangest of angles; but there is a power and grace behind that gangly frame and power that betrays his innocent and childish demeanour in those dark eyes. Itachi knows that those eyes can instil fear into even the greatest of ninjas, he knows what those eyes can do, and that is what has always drawn Itachi to him. It is also the reason why they are both here tonight – although Shisui does not know that; not yet.
The night is hot and quiet, and the only noises either of them can hear are the cicadas singing and the quiet gurgling of the river current dancing around their hips. It is late, and everyone is either at the meeting or at home in their beds. Itachi and Shisui should be there as well, and Itachi knows that their absence will be noted, but he no longer has time for caution. War is brewing, and he can sense it in the tenseness of his father's shoulders when they sit down to eat, can see it in the eyes of every single Uchiha shinobi. He even sees it in Shisui's eyes, and it breaks his heart.
He kisses Shisui, gently at first, and it is only the slightest of brushes against his lips; soft and barely there, like the wings of butterflies against one's skin. But then it becomes needy, desperate even, and Itachi presses his lips hard against Shisui's, demanding, begging, pleading. Shisui kisses him back with equal fervour and their tongues become intermingled, pushing back and forth as if it is a struggle with only one victor. He feels the desperation building up inside of him, and it forms a cold, hard steel ball in the pit of his stomach and just sits there, weighing him down; all the pressure he's felt the last couple of months combined with his guilt. The shame of betraying his family builds up, and up, and up, until it threatens to burst out of his chest with his racing heart and swallow him whole.
He feels the tears slide down his cheeks as his hands tremble. It is a struggle not to push Shisui away and try to forget this whole thing, to just go back home to his family and his brother and pretend that everything is normal, pretend that everything will be alright. But he knows it won't, can't ever be, and he knows that this is the only way he can protect his brother. It is a sacrifice; one that he has to make.
His fingers twitch as they slowly trail down Shisui's face. He lets them linger at his jaw line for a moment, tracing the still-boyish curve lovingly, before they continue downwards and stop just at the base of his throat, thumbs resting gently in the hollow. There is a moment where he pauses, and the world seems to come to a crashing halt. He does not feel Shisui's lips on his own, or the river lapping gently against his thighs. He cannot hear the cicadas. For a pure and blissful moment, there is nothing.
His fingers twitch again, and suddenly he's back. Shisui has noticed that Itachi has stopped responding to the kiss and his hand brushes against his cheek, drawing back slightly, in surprise, when he feels the wetness of Itachi's tears.
"I'm sorry," Itachi mumbles against his lips, and Itachi knows that it will be for the last time.
Shisui draws away to look at him, to ask him what is wrong. Their eyes meet again and Itachi knows what he has to do, even though it tears at his very being to do.
"I'm sorry," he whispers again, and he has never meant anything more than he does in this very moment. He pushes his fingers hard into the hollow of Shisui's throat, and his eyes widen as Itachi pushes him backwards into the water, holding him there. Itachi is not overly strong, and even with the advantage of surprise working in his favour he still has to use all of his strength and body weight in order to keep Shisui's mouth and nose underneath the surface as he struggles and thrashes wildly against his hands. Itachi's pale fingers are tight against his slender throat and he pushes down hard, even though Shisui's air supply has already been cut off and there's no need, anxious to be over with the deed.
He squeezes his eyes shut as he feels cold fingers reaching desperately at his sleeves, at his arms, at his face, anything he can touch. He tells himself it's to protect himself against Shisui's sharingan – and that's partially the reason, Itachi is not stupid – but he knows that deep down, the real reason is that he cannot bring himself to look Shisui in the eyes in his final moments because he knows what he will see there; the pain, the betray, the hatred. He cannot bear to see it, not from Shisui.
The thrashing has decreased now, no longer so frantic and desperate, but rather helpless. Itachi shudders as he feels Shisui's fingers on his face, and they brush across his eyelashes for just a moment before they drag wet trails as they slide down his cheeks and land with a splash into the cold water, no longer having any strength. He knows that it won't be much longer now. Soon Shisui will stop struggling completely and fall into the blissful sleep of death – or at least, Itachi hopes that it is peaceful, but he can't help but wonder if that's just another lie.
A moment later he can no longer feel Shisui struggling beneath him, and it is another minute longer before he can finally bear to open his eyes. He looks down, holding his breath, and he is met by the black pools of Shisui's eyes; wide, cold, and dead as they stare back at him, caught between a devastating mixture of fear and anger that affect Itachi to his core. His pale and chapped lips open in a perfect "o" underneath the water, his face wavering with the same hypnotic rhythm as the reflected moonlight.
"The price of the mangekyou sharingan is to kill the one you care for most," Itachi recites. His voice is charged with grief and he doesn't bother to stop the tears that fall, can't stop them even if he wanted to. He looks up at the full moon, its pale beauty mocking him in the dark sky, and his voice nearly breaks when he speaks again.
"You have always been that person."
He feels a break within himself, then; the fleeting remnants of his humanity vanish, tangibly, like the life in Shisui's eyes. This is his sacrifice.
Just in case someone asks me about this, cicadas don't usually sing at night (although I think there are some that do). I'm not an entomologist, and I have no idea what the behaviour of cicadas in Japan is like, so this is merely guess work on my part. However, I've gathered in my "research" (google) that cicadas will sometimes sing if there is a light source (i.e. a full moon), and hot weather. There are some other factors, but these are the two that are applicable to this piece. 8D