As she looked down at their hands, she felt incredibly confused and touched at the same time. He trusted her enough to give her a laster screwdriver, knowing that she could turn around at any second and use it on his Companions... or him. But even so, the Doctor had given it to her anyways.
"Thank you," she replied softly, craning her neck and standing on her toes to give him a light peck on the lips. "This means a lot to me. But you're right... they don't understand us. In many ways, they never will. Our relationship has always been complicated. These memories though... do you mean memories of things that are still to come in the future for me, or memories of our past? Possibly even both?"