> He lies beside me on the sofa and nibbles at my fingernails.
Ahh, bless him :)
Buster is a nibbler, he likes to nibble toes, socks and legs, basically anything in reach when he's laying at your feet. He does get a little carried away sometimes when nibbling socks, if he gets a good grip he'll pull it off and chuck it around like a trophey :-D (while laying down of course as he's soooo lazy)
Oh, he also nibbles the cats fur

it looks bad to see such a big dog with his chops nibbling away at the cat, but he's very gentle. Trying to get him out of the habbit of nibbling the cat but it's hard as she'll sometimes get cross with him, which he thinks is great fun. If shes acting all 'prim & proper' she'll ignore him, so it's easy to get him to stop & do something else instead.
I'm sure it's an attention seeking thing - how can you ignore being nibbled on!