He didn't know why he said it.

Really, even now, after everything was over, and he miraculously had time to consider his actions, relive the panic and then the icy cold of certainty that contrasted with the inferno of radiation poisoning him as it cooked him from the inside out, he didn't know why he said it. He knew his mind had been fogged, he had thought he was going to die after all, but still. Why had he said it?

"I want you to know why I went back for you. Why I couldn't let you die."

He hadn't chosen those to be his last words. In fact, he'd never thought about what his last words would be, not even when he ducked into the warp core, not even as the stinging turned to burning and then to a gentle tingle as his organs began to shut down. He didn't think about his last words until he was lying there, waiting for his lungs to collapse, waiting for his heart to fail. Staring at Spock.

He didn't think about his last words until he was staring at Spock.

"I want you to know why I went back for you. Why I couldn't let you die," his memory began to get hazy at this point, Bones told him it was because the radiation had breached his skull and his brain was beginning to cook.

But he does remember the tear. And he does remember what Spock said.

"Because you are my friend."

His mind screamed no as his right lung collapsed, sealing off his last words forever. Breathing became a struggle that he lost along with all feeling in his legs as his vision began to go white (you cooked your cornea, Jim). He couldn't speak, but he could do one last thing.

He lifted his arm and pressed his hand to the glass, smiling slightly as Spock pressed the Vulcan salute to the other side. He focused on that image as the edges of his sight burned away, forcing the last of his energy into fitting his hand to Spock's.

That was the last thing he saw, their hands separated by three centimeters of plastic.

His vision stolen from him, he turned his face to where he knew Spock's was, struggling for that last breath, imagining those brown eyes locked on his.

Spock.

And then he died.

Alive again, he had what no one else in history had. Time to think about his death. Time to think about his last actions. Time to relive his death over and over, but he knew he'd get over the PTSD eventually. Time to think about his last words.

If put in the same situation again, he wouldn't change but one thing, even if there was no blood to bring him back. He wouldn't have paused, wouldn't have let Spock speak, wouldn't have waited. He would have just spoken, let the consequences be what they may.

"I want you to know why I went back for you. Why I couldn't let you die. Because I love you, Spock."