The following two situations:

1. She also thinks she is an "aunt", and sticking out her tongue can reduce her age, make her look cute and proud, and at the same time narrow the "age gap" with you.

If you like her, please touch her nose and praise her for her cuteness. If you don't like it, just watch the show.

2. She doesn't feel like an "aunt" at all, sticking out her tongue is the embodiment of her youthful vitality. You may have a good impression on this person.

It's impossible to call women "auntie" when you are unfamiliar, and you won't give them nicknames if you don't like them (hehe). There are many expressions of sticking out your tongue, so I suggest you distinguish them. You are welcome.