Annoying toddler habits: Biting, pulling, and growling

I'm so embarrassed to say this, but my son has an awful, annoying habit: he bites.  Yes, he uses his 7 little teeth to bear down on the skin of my thigh when I'm sitting down.  And it's unprovoked!  It's not as if I took away a toy and he threw a tantrum and bit me.  He'll just come up to me while I'm sitting down, put his head on my leg, and as my heart wells with love and admiration for my child and before I can pick him up to cuddle him, he turns his head and, while still maintaining eye contact with me, he goes ahead and bites me.  Sometimes hard, sometimes soft, but he always checks to see if I'm looking at him.  I guess he gets a perverse pleasure from seeing me recoil in horror.

This is what he looks like when he puts his head on my leg.  This is when I'm all like, "Awww...look at how adorable he is!  We owe it to ourselves, our family, and this country to make more children like him."

This is what he looks like seconds before he chomps down on the soft fat of my inner thigh.  Terrifying.

I'm worried that the habit won't break and that he will start to bite whenever he's angry.  Already, when he starts throwing a tantrum he'll throw whatever is in his hands or squeeze it really hard.  Poor Pirate.  If he's anywhere near Desmond when Des is throwing a fit, Des will run to him, grab a handful of his loose, fatty skin and fur, and squeeze it.  My poor dogs put up with a lot from Desmond.  I mean, he tries to "pet them" and instead, hits them really hard in a petting motion.  He also likes to poke Pirate in his butthole.  No joke.  I don't need to worry about how the dogs will be with Desmond anymore: they're fantastic around him.  I need to keep an eye on Desmond to make sure that he doesn't permanently blind Pirate or maim Hanzo.

The beginning of Pirate and Desmond's tumultuous relationship.

Pirate's face shows that he's starting to get an inkling of the abuse that's coming.  On another note, look at how disproportionately LARGE Desmond's ear is compared to his face!

Oh, and get this.  Before, when Desmond didn't want something, he'd start shaking his head no and start crying.  Now, he'll preface that with a growl.  Seriously.  A bona fide rumbling growl that emanates deep from within his little chest and grows into a scream.  It's kind of terrifying.  I don't know what excuse we would give to people who witnessed that if we didn't have any dogs.  I swear he's getting it from Hanzo and Pirate.  Weird, huh?  Next thing you know, Desmond's going to be picking his leg up and itching himself on his face.

We need to expose him to more children.