Girl's Behavior

What does it mean when a girl sends you a smirking emoji face?

I've only just met this girl at university and over text she said '' I can be waymore of a tease than that. I then said ''I'm trying imagine how so haha'' she replied with '' haha you'll have to keep imagining because its my secret (smirking face)

Yes we have been talking a lot recently as well. We don't talk university work either.
What does it mean when a girl sends you a smirking emoji face?
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