The act of
running to a person and hugging them tightly with enthusiasm, followed immediately by rubbing or burrowing
one's face into the recipient's
neck or face.
This is usually done out of love or greeting, to express emotion and fondness.
Friend 1: Sorry about that, I didn't mean to take so
long.
Friend 2: *fruffles* I missed you! Where have you been!?
Best Exemplified in the
movie Ponyo, when Ponyo is reunited with Sosuke in her human form.