"Thank you," Sherlock murmurs into the darkness after everyone has left with their promises to check in again on the next night. That's it now for him, living his life predominantly at night, needing the black-out curtains pulled to move around during the day, never seeing the sun again except on television. It makes him a little sadder than he thought that it would, but he'll adjust.

John sighs, carding fingers through Sherlock's hair, relieved to be back to this familiarity even if so many things are different now. "You don't have to." He's quiet for a moment before he continues on. "You know, you weren't breathing when I pulled you out of the water, and as I tried to get you to start again, I realised that I'd change you anyway, whether you'd asked me to or not. And I know it sounds selfish but, I couldn't bear to lose you, Sherlock, not so soon, not like that. Not ever, maybe. The thought of forever without your smirks and your sarcasm and your black moods, it's ridiculous but I couldn't bear it. I know that, now."

Sherlock opens his eyes and reaches up to pull John down. "I remember seeing you, and everything hurt so much and I wasn't sure if you were real or not, but I thought, well, if I'm dying, at least you'll be the last thing that I see, my last memory whether real or not. But I didn't want to leave you behind, didn't want to put either of us into that position." He swallows, feeling like crying but not being able to anymore. "I was just glad that you were there, with me."

John presses his lips softly to Sherlock's not knowing what to say, not wanting to think about those horrible moments when he was so sure that he was going to lose this wonderful man without getting to at least try to save him first. And that is how they pass this first day of undeath, gentle kisses and murmured words, each holding on so tightly out of fear and hope and relief.