In British English, "to rabbit (on about something)" is "to talk", and it appears that it comes from rhyming slang ("rabbit & pork" = "talk", shortened to "rabbit"). However, I seem to have heard or read "rabbit" used in a sexual or semi-sexual context, and I think it was American English. Apart from the obvious association (rabbits are reputed to be keen on it, hence "breeding like rabbits" and so on), I was wondering whether there would be a more specific meaning. If I am completely off-target, apologies. And a Merry Xmas too.