Blood Will Tell

This came about mainly from wanting to rationalize vampire mythology with a plausible mechanism (background notes):

              EXT. CITY STREET -- EVENING

              Alex picks up Ben

              INT. - ALEX'S BEDROOM -- EVENING

              Alex is fucking Ben.

                                    BEN
                        Ah!  Ah!  Ah!  Oh no!  Don't make 
                        me...  Ahhhhhhhh!

              Ben's warning is too late: they both cum together, and in 
              first of the orgasmic convulsions, Ben pulls Alex down to 
              him and bites Alex on the neck, holding him there clenched 
              and biting through the duration of the orgasm.  As the 
              orgasmic convulsions wear off, Alex's take on the chaotic 
              form of real convulsions, growing back in intensity.  
              Keeping clenched, but releasing the bite (revealing a 
              moderate amount of blood), Ben rolls over on top of Alex, 
              holding him down until the convulsions subside.  He 
              collapses in place on Alex, sobbing.

                                    BEN (CONT'D)
                        Not another one!  

              INT. ALEX'S BEDROOM -- EVENING

              Ben is sitting in a chair, head down, next to Alex, who is 
              still lying on the bed.  Both are still naked and little 
              appears to have changed beyond Ben's moving to the chair, 
              and there is a KNIFE on the nightstand.  Alex stirs.

                                    ALEX
                             (groggy)
                        Owww, what happened?

              Alex notices Ben sitting there as he becomes more lucid.

                                    ALEX (CONT'D)
                        Man, did you really bite me?  Gawd, 
                        what's that stench?

                                    BEN
                        How do you feel?

                                    ALEX
                        Like my body has been torn apart 
                        and put back together..

                                    BEN
                             (muttering)
                        It has

                                    ALEX
                        And it stinks like it too!  What?

                                    BEN
                        Look, trust me --- I'll make sure 
                        no harm comes to you.  Go back to 
                        sleep and I'll explain everything 
                        when you've recovered more.

                                    ALEX
                        OK, the fact that there is 
                        something to explain means that 
                        there's not a chance I'll be able to 
                        go back to sleep until I know what's 
                        going on.  My whole body is aching, 
                        but somehow it feels better than 
                        ever despite that, so spill it.  
                        What the hell's going on here?  You 
                        did bite me...

              Alex feels his neck --- nothing.

                                    ALEX (CONT'D)
                        Odd, I'd have sworn you practically 
                        ripped out my throat.  I'd better 
                        not have a hicky though...

                                    BEN
                        Look, I'm sorry, I didn't mean for 
                        it to happen.  It's just that I 
                        didn't expect it --- no one's made 
                        me cum fucking me in...well, a very 
                        long time.

                                    ALEX
                        What's that got to do with it?

                                    BEN
                        All right, but first, so you'll 
                        believe it's real...

              Ben picks up the knife on the nightstand and quickly cuts 
              his arm, then holds up the cut so Alex can see it heal in 
              seconds.

                                    ALEX
                        Whoa...how'd you do that?

                                    BEN
                        Please don't freak out now, most of 
                        what you've heard about us is wrong.  
                        I'm a vampire.  And now so are you.

                                    ALEX
                        Yeah, right, and I'm the queen of 
                        England.

              Ben, with the knife still in his hand reaches over and 
              slashes Alex's arm.

                                    ALEX (CONT'D)
                        Ouch!  What the...

              Alex's arm heals about half as fast as Ben's did --- still very fast though.

                                    ALEX (CONT'D)
                        Fuck me.

                                    BEN
                             (smiling)
                        Not yet, you need to recover some 
                        more.

                                    ALEX
                        Very funny. 
                             (beat)
                        Shit.  I liked the sun.  And I 
                        can't very well go around killing 
                        people.  How am I supposed to 
                        survive?  How do you survive?

                                    BEN
                        There is a network of farms that 
                        cater to our needs, but in a pinch, 
                        you can feed directly from animals.

                                    ALEX
                        How do I keep from creating a herd 
                        of vampire animals?

                                    BEN
                        You have to 
                        explicitly want to make a vampire, 
                        unless you're having sex, then it's 
                        unfortunately reflexive.  You'll learn how to consciously

control your fangs, which inject the virus. Obviously, it's not something done lightly, and I didn't mean to do it to you. Sorry about that...