They check things out with their mouths, especially when younger, so nibbling is not an act of aggression so much as exploring.

Spockie used to love my feet and ankles, lick them a lot, and then nibble. I would let out a high pitched yelp, he would look up, actually look sorry, and go back to just licking. You can let Edmund know that it hurts you a bit, and he will be startled into backing off the bites most likely after a few times.

I agree. Let him know what’s ok and what isn’t. He’s obviously a sociable guy which is great. Some rabbits do little biting/nnibbling when grooming another. With 2 rabbits, they’ll let each other know if it’s ok or not but shrinking away or letting out a squeak. Immitate this and he may be a bit gentler with his interactions. So either let out a short squeal or briefly push his head down when he bites.  Try avoid petting him directly afterhe does it otherwise he may learn that biting = getting groomed and could become his way of requesting grooms.

My Doe likes to dig and nibble at my clothes and my Buck has a habit of “saying hello” or “move” with his teeth on his way past. Usually it’s my ankles or hip if I’m sitting that he targets and it’s just a light grazing but it still catches you unawares sometimes.

Are you familiar with Language of Lagomorphs? It’s a site that helps understand rabbits. http://language.rabbitspeak.com/rabbittalk.html

This is sooo common with young bunnies. Otto nipped at me all the time when he got over excited and thought we were playing. What I did was walk away and turn my back on him. I would ignore him for maybe a minute or two, then go back in his pen. If he did it again, I would get up and walk away. Since it doesn’t sound like he’s biting you to get rid of you (like territorial biting) but rather out of curiosity, I find the ignore technique teaches them that if they bite, their playmate leaves.