Rose has been avidly watching the Doctor lick around and around that ice cream cone for what seems like entire lifetimes, his tongue darting out to catch every drip before it falls. She never expected to associate something so delightfully sugar-laden with torture, but she's sure this must qualify. She can't pry her eyes away, though. She doesn't even really want to.
But damn his obvious oral fixation this regeneration.
Eventually, though, enough must be enough. Luckily, she knows one sure way to stop him from continuing the tease.
She leans close and gathers some of his ice cream on her own tongue. He's surprised to find her face suddenly so close to his, but not half as stunned as when their cold tongues meet halfway around the cone.
The ice cream falls to the ground, finally completely forgotten, and Rose can't help but grin triumphantly against the Doctor's lips.