I'll start to sing and you just follow the sound of my voice
Maybe she was a little distracted by her new surroundings. Or maybe she hadn't really been paying too much attention in general, but she had found herself wandering for a good few minutes before she remembered why she had left the comfortable room in the first place. A flash of realisation crossed her features as she tapped her chin thoughtfully, listening out for the sound of the Captain's voice.
She continued to wander until she heard that familiar voice. The song however? Not so familiar... or maybe he had sang it before when he was drunk? She couldn't remember. As she drew closer to the door, she heard the last few pieces the Doctor had to say, particularly a line about an 'old girl'
She stopped just past the doorway and looked at the Doctor, a grim expression crossing her features. "Baka, who are you calling old girl?" she said dismissively as she walked past him. There was sake to be drunk after all!