I despise Twilight and most of the things it stands for, but this is somewhat understandable (at least to me).
I'm somewhat Goth and I'm into bloodplay (along with a great deal many other things), so I get a bit of flak from the "vampirism" angle, but it's really not that...it's just an irony that I was born with fangs
I can't explain why, and this forum most likely isn't the correct place anyway, so I'll be very brief and try to keep it PC, but I guess it is related to blood being the life force/heart is the source of love; both embody passion and are intimately personal. Thus I find it adds something to the sexual experience. It's just something I find hot; but for the love of god you'd never do it with random strangers due to all the risks involved.
Closest analogy I can find (that has come up on this forum before) is that several members have commented on the experience of sex combined with various drugs. Most people would agree taking hallucinogenics or stimulants is pretty dangerous/stupid, but many enjoy the experience and sense of taboo.
And for the record, you don't want to go for wrists or neck (arteries obviously, but veins cause surprisingly urgent problems if cut, especially if the pulse is racing). The shoulders however are very rich in blood and heal well with little incidence of infection. Knives/daggers work much better than razorblades too.
Therefore I can understand the fankids (some of whom really think they are vampires which is saddening) taking this to the level of wanting their favourite actor to drink their blood/they drink his. Is it any different to fantasising about a porn star bobbing about on you, or Lara Croft, for ordinary folks/geeks (respectively)? It's just an embodiment of sexualisation.
I guess actually going up to him and asking him to do it is wierd (and awkward for the normal population, like watching a stereotypical 80s computer nerd chatting up women), but fantasising I can accept - everyone has their kinks and quirks.
Holy crap, I think I just indirectly defended Twilight fans. I never thought that'd happen *gargles with whisky*
So I'm going to throw in a semi-serious vote of:
Biased poll - where's the option for those of use who like blood but are not associated with that Twilight crap?