"Oi..!"

The Doctor just makes a face at her like the most offended nine-year-old ever, pointing an index finger at her warningly, like he might really super scold her if she keeps it up, when she gives that look at his eyebrows. Hardly the first time he's been a bit defensive, but this is maybe the silliest he's been about it... and maybe a rival to the silliest she's seen him, which isn't a small feat.

He does get just a shade more serious at that bit of concern, even if he's at the same time amused at her picking up "spoilers" so quickly.

"...ha, well... something like that, yeah."

He raises his eyebrows at that last bit, smiling one of those enigmatic smiles she probably hasn't seen on most of his faces that she's encountered--except maybe his older one. He can't really resist, though, given how long it is 'til the next time he sees her.

"...look who's talking. Anyway, thanks, I appreciate it, nice to know my future's in good hands."

Meaning hers, of course, because the Doctor can't just go complimenting himself across regenerations.