Try to pull Keira's sweater free.

Moving quickly, you bend to release Keira's sweater. You pull, but the fabric merely stretches, the sharp corner of the shelf holding onto the cotton firmly.
"C'mon, c'mon, c'mon!" You hiss under your breath. Keira has started to sob again. You grunt and strain, but it is no use.
Through her tears Keira says: "Sarah... J-just go." You look up into her face. Before you have a chance to respond you hear a voice behind you say:
"What do we have here?" You spin to see Harriet. You always remembered her as the ultra conservative, ultra religious type, but now her body is fully on display. Her classically east Asian looks are framed by her dark lustrous hair which comes to her shoulder. Her bare body is deathly pale and her dark nipples stand out on her round, firm breasts. Her hairy cunt glistens. You meet her eyes and see they have become a deep crimson.
"Aren't we lucky to have found you." She says, glancing up behind you. You turn to see Alex standing tall on the tipped shelf, Karen crouching next to him, one hand curled around his bear leg, the other waving sultrily. They are also equally nude and fanged. Keira, who has been tugging at her sweater this whole time, finally rips it free, and presses up against you for comfort.
"Mmmm, what shall we do with you?" Harriet says, sauntering forwards, her clawed hands sliding over her smooth skin seductively. "Well since you seem so attached to one another, how about we turn you together, twins in transformation."
"Ooh I like that idea." You hear Karen croon. "Very poetic."
Alex hops off the shelf, eliciting a yelp from Keira, and begins to stalk the small distance towards you. You lock eyes with Harriet once again.
"Please Harriet, we're friends! Don't do this..." Harriet laughs heartily, her breasts bouncing with each exhalation.
"You're right we are, but even if we weren't I would still offer you our gift." Then, faster than you can think, she rushes forward. A scream from Keira indicates Alex has done the same. Before you can react, Keira is pulled away from you and Harriet has her arms wrapped around your waist. You feel her breath on your neck, but are transfixed with Alex. He has his arms wrapped around Keira and is kissing her deeply. Your friend struggles for a while, her arms punching him uselessly. Then, much to your horror and surprise, she relaxes and begins to respond in kind. You feel Harriet's hand reach under you, her claws brushing your cunt through the fabric of your trousers.
"I bet your sopping wet..." She whispers into your ear, and you try to hold back a whimper. With a painful yank, she digs her claws in, ripping your pants in half so that the legs still remain while the waist band folds away to reveal your now bare crotch. Harriet puts a hand on the back of your neck, pushing you forward slightly so you are bent 45 degrees. Everything in you screams to fight, but somehow you can't seem to muster the strength. You can see that Keira has lost her bottom half and is bent in a similar fashion to you. Alex is entering her slowly, her face a mask of bliss. She makes eye contact with you and you think you see her returning, a semblance of awareness and fear in her eyes, then it all floods away as Alex thrusts hard just as Harriet plunges her fingers deep inside of you. You both squeal in pleasure and terror as the vampires stimulate you mercilessly. This continues for a moment, then Alex tears Keira's ruined sweater and shirt away to reveal her small breasts. Harriet follows suit and soon you too are naked. As you come closer and closer to climax, you feel Harriet loom over you, her crotch brushing your hip, her nipples tickling your back. At the same time, Alex moves forward. You look into Keira's tear stained eyes knowing this is the end. You smile, and find it come surprisingly easily. Then they bite. You watch as Alex's fangs dig in, a mirror of your own situation. A small glob of blood drips from your friends neck. You climax, and through the pain you push forward and kiss Keira passionately, then you are met with darkness.

When you awake, the first thing you notice is the sound and smell of sex. Groggily you look over to the overturned shelf. Alex is dutifully thrusting into Karen, who appears to be enjoying the movement immensely. Harriet is cross legged, her fingers grabbing at her sopping cunt frantically. Her lips are still slightly red from your blood. Finally you turn, to meet eyes with Keira. There are no more sobs, tears or begging. In her eyes are only lust and hunger. You slide forward, wordlessly embracing her, entwining your now perfect bodies together, seeking out and touching each nook and cranny with talon, tongue and cunt. Shortly, the other vampires join the embrace and it is not until hours later that you all rise together, your lust sated, for now.