Disclaimer: If I owned Yugioh, well, let's just say that I wouldn't have watched it as a child.
Warnings: Blood, angst.
"Seto… it hurts," Mokuba Kaiba cried, his voice dry and scratchy.
Seto Kaiba frowned grimly at his younger sibling's state. If one looked into his blue eyes, they'd see nothing but the grave absence of hope. "It's okay, Mokuba," he assured, sounding monotonous and unconvincing. His voice started to tremble. "It'll all be over soon."
The next thing the younger brother said was in a broken, whimpering whisper. "When? I… can't take this anymore! I want to die, it hurts so much!"
"Mokuba…" Seto clenched his teeth forcefully and squeezed a dagger in both hands for dear life. He was shaking violently. Seto held his breath as he positioned the dagger over his precious younger brother's chest. Seto couldn't decide if he saw relief or fear in his younger brother's eyes. Unable to bare keeping his dripping eyes open, Seto closed them tightly. He plunged the dagger into Mokuba's chest with all his might, trying to convince himself that his physical strength would build up his will.
Mokuba released an agonized choking sound and Seto couldn't hold back a painful sob. He couldn't open his eyes, couldn't bear to look, couldn't even think about living with himself after this. He tried to remind himself that it had to be done, that Mokuba's prolonged agony was worse than this and that there was no cure for his painful illness. Even with help from the world's finest doctors money could buy, nothing could numb Mokuba's pain without taking his life.
It had to be done.
It had to…
The thick scent of iron filled Seto's senses. He opened his eyes to see his precious little brother's bloody, lifeless form. Once he caught sight of Mokuba's pained, unblinking eyes, a powerful urge to regurgitate his cramping insides overwhelmed him. He wanted to scream, but it came out more like a gurgled choke.
Black splotches invaded Seto's vision, and his head buzzed. The blood drained from his brain, leaving him so lightheaded that he lost consciousness.
When Seto woke up in his brother's cold blood, his heart stopped beating. He felt like he was the one with the dagger in his chest. Seto started hyperventilating, before he let out a powerful, throaty scream.
After an indefinite amount of time of sobbing, Seto felt a persistent need to tend to his little brother. He left the room to get a rag, a bucket of water, and a formal change of clothes for Mokuba.
When Seto returned, he tugged the dagger out of the child's chest and set it to the side. He then stripped Mokuba's corpse. He would have left his underwear on if his little brother hadn't soiled himself before he died.
Seto threw all the fabric onto the floor, including the filthy bedding. He cleaned away all the bodily fluids covering his little brother's body with the rag, dipping said rag into the bucket of water and squeezing the fluids out in between cleaning him until the water in the bucket was a dark brownish red.
Once Mokuba's lifeless body was clean, Seto looked at his face, almost expecting some sort of thank you. That is, until he saw the pained look still in the bloodshot eyes. At that point, Seto started to tremble, and he closed Mokuba's eyes, hoping it would give the younger Kaiba peace.
He dressed his little brother's remains in his tuxedo - the one Seto wore to their parent's funeral when he was about Mokuba's size and age. It was only a little big on the younger Kaiba.
Seto stared at Mokuba for a long while. It was almost like he was sleeping, only he didn't seem to be having pleasant dreams. Eventually, it became far too painful for Seto to look at him.
Seto threw all the soiled fabric into the flames of their fireplace and watched as it all burned.
Even if Mokuba would have had to suffer longer, at least he'd be breathing longer. Maybe death was worse.
Mokuba was gone, and he took with him Seto's heart and soul.