No, but they are sins which Jancarius mentioned wanting to base the WCV families in his game around. Really the only difficult one there that I can see is Pride. How does someone Proud themselves to death? The closest I can think of is "too proud to stop doing something bad for them" or possibly "too proud to ask for help".
Organ failure from lack of life energy.
Well, as was mentioned, it may be the "first kill" which brings a WCVirgin over into its full abilities, but it isn't the physical death that they really feed on. They just cause so much life energy loss that the victim's body dies, unable to support itself.
So there are two questions, and the answers, as I understand, are:
1) What does a WCV victim look like?
Answer: like any other WCV victim.
They prefer people who are displaying particular types of emotion, as they feed more effectively in those cases. They have learned to mask evidence of the predation by inspiring their victims to display behaviors symptomatic of an unrelated issue (suicide, in some cases), or fright (scaring them into displaying a frightened face before they die), but these are decoys, red herrings. Ultimately, they all die of life energy deficit.
2) How does a WCVirgin get its first "kill"?
Answer: like any other WCV victim.
Without knowing it, they drain the life energy from a suitable candidate. The candidate may have been a "prime target" owing to a particular House predilection towards a particular emotion, but ultimately that first death is simple energy drain.
So that means that, if a WCV never learned how to pass in mortal society, how to pick suitable candidates, or disguise their kills, there would just be a bunch of victims in its wake with no obvious source of death, most of which would be pigeonholed into "heart attack."