Sometimes eBay notices members with a lot of negs, and NARUs them even before they accumulate any FVFs. I've had buyers, obviously just there to buy stuff and never pay for it, with a -4 rating. They buy something from me, don't pay right away, so I give them a fifth. Before they've even been registered 3 days, they're NARU. I think eBay notices extreme cases of negative feedbacks. Or, perhaps someone pulled their contact info and reported it as false.
can-import, your recourse against this idiot is to get them NARUd and then contact PS support to get your neutral feedback removed. Feedback left within 30 days in either direction of a member being NARUd is elligible for removal. See the feedback removal page for details.