It hit him like a dull blow to the stomach, faint, almost muted, but hard. Existent. Constant. Proof. Proof that it had happened. Proof that he had done it. Proof that he killed Karai. He could remember it but it was so unreal, so dreamlike, his mind had given the memories a fuzzy quality, made them easy to forget and hard to take seriously. But he knew it was real. He could see it in Mikey's eyes, Donnie's speech and Raph's stance. And he could feel it in the pit of his stomach, a constant feel of almost throwing up, his insides churning as he tried to focus. Splinter knew. He knew Leo had killed Shredder's daughter. Leo could tell by the sympathetic glances, the kindness that was even more evident and the way he never spoke of Karai again.
Leo couldn't think. The way things were he couldn't focus, the pain was a constant, dull, ache and he wished he could just sleep. Wished he could blackout forever. The Shredder would want revenge. Leo was surprised he hadn't done anything already. Leo couldn't move. His body was hard to control and everything he did seemed to be in slow motion. It was like he was watching himself from afar. He didn't feel centred in his body.
Several months later Leo laid in his bed unmoving. The Shredder had taken his revenge. It was all Leo could think about.
It had been raining. Raph had finally managed to convince Leo to leave the lair and the four of them had been running. They jumped over rooftops and best of all they encountered no one. Which meant no fights. They had been halfway to April's house when it had happened. The Shredder himself. He had landed in front of them, stopping them in their tracks and then he said it. Karai had been Miwa. Splinter's daughter. Leo had killed Miwa Hamato, his father's blood. He had taken the life of not only the girl he loved but the last memory of Tang Shen. His father would never forgive him. His father should never forgive him. Leo was going to make sure he suffered for what he had done.
As he lay there in the dark Leonardo Hamato promised himself no forgiveness. He would spend his life in misery. He had taken Miwa's life, Splinter's joy and his brother's sister. He was going to give himself the worst punishment he could image. He would keep living.
That night as he cried himself to sleep Leo clutched tightly his mask. His mask that was blue as sorrow.