Tallullu - OMG, the whole grooming yourself cracked me up. I don't feel so kooky anymore because I do that too!! Where'd you learn to do that? (just common sense by learning rabbit behavior or ???) That's just what bunnies do when they are getting to know each other and want to let the other know that they mean no harm. You're one smart humanbunny!
When I am meeting a new shy bunny at the shelter, or when I am pet sitting, to help them get used to me, I do that too because that is how bunnies communicate to each other.
We are bonkers! But smart bonkers. Big difference. 
When he nips, also try and do the high pitched screech.