It was much later than usual when Sherlock and John finally carried a sound asleep Rosi - Roz off to bed, and they were finally alone.
"Peter -"
"I know -"
"Sorry, you first -"
"No -"
Peter took Gamora's hands in his and stared at them for a long time. "You can't ask me to - what you made me promise you - you just can't do that again. I know why you asked me, I do, but you can't. I can't be the one, Gamora. I don't understand what's going on right now - I don't usually, any way, I just keep going, it's all I know to do - but somehow - we ended up in this -" He looked around the flat and shrugged. "- sweet, crazy place together - we're safe for some reason, wiser men might know why or not, all I know is that I was responsible for ending half the universe when I thought you were dead. I thought I'd never see you again, I watched our friends get turned to dust on a burned out planet, and I - I was reduced to ash, Gamora, only to end up in London to find you here. I can't lose you again. I thought - I thought I knew how important you were to me, but I didn't - I didn't -"
She shook her head then kissed him gently, carefully, as if he might turn to ash in front of her. "You're really here."
He nodded, and let her hands go, but only to thread his fingers into her hair, and pull her closer. "Just promise me -"
"I won't, Peter. I swear. Whatever happens next, we do it together. All the way." He backed away as he felt her tears fall over him, and pulled a rather tattered, but remarkably clean towel from his pocket, and tenderly dried her face, then kissed her forehead. "How?" She whispered.
"I dunno, somethin' Yondu always said, 'Never lose yer towel, son.'" He shrugged and put it back in his pocket, his eyes never leaving hers. "So, we could do some more colouring - and there are some cook - uhm, biscuits that you haven't finished off yet, or we could -"
"Go upstairs?" She suggested with a smirk as she took his hands, and began walking them backwards towards the stairs.
"I suppose... though they do have a television, and I haven't seen one of those since -"
"Peter Quill." She narrowed her eyes at him and grumbled under her breath, but kept moving.
"Lead the way, love."
"Half the universe, really? You do love me."
"Duh." He rolled his eyes at her, and pulled her into his arms again. "Yes, Gamora, I really, truly, desperately love you."
"Good. Just wanted to be sure." She grabbed his hand again and pulled him up the stairs to the bedroom, then quietly closed the door behind him.