Picking your teeth
When someone says they're picking someone's teeth, they're changing their mouth to get you to say something that they want you to, usually for a setup or to make them mad.
Sorry I have to study for a couple of hours.
Sounds like a lot of fun! Are you having fun?
No??
Haha yeah I'm just picking your teeth.
Sounds like a lot of fun! Are you having fun?
No??
Haha yeah I'm just picking your teeth.