"Huh?" he says, turning back to Rosie. "Oh, um." He almost doesn't want to say, but decides it's better not to keep it from her. "It's a combination of things, actually. She's, like, fond, and kind of amused, and..." He trails off, eyes going a little unfocused. "Oh. And... I think that's nostalgia? It's, like... Warm, and happy, but also sad and a little lonely." He clears his throat and adds in a whisper, "I think she thinks we're together, and it's, like... reminding her of when she had someone?"