Maybe it's a "simon" issue
My 1.5 year old Simon drags Hallie by her head. Yesterday I caught him nibbling on her face. It has gotten out of hand once or twice but they are usually just playing. Every once in awhile it gets rough and I have to separate them but lately SImon just nibbles and Hallie lets him. I think it is his way of trying to get her to play with him when he's bored. Usually if I make a loud noise they will let go of each other
Silly dogs