Facial Spelunking - A dirty habit where you stick your finger in someone's nose

A dirty habit where you stick your finger in someone's nose just to see what gross stuff comes out.

My little brother did facial spelunking on my mom. She threw a pillow at him.

At the party, my friend did facial spelunking on the DJ. It was legendary.

During the movie, I did facial spelunking on my brother. He was mad for the rest of the night.