Jen’s arousal clouded her mind as she began to string together a curse for Jess.
“Um... For your transformation...” Jen began, feeling goosebumps along her chest and thighs.
“Your left head’s tongue will turn into a penis.”
She felt silly saying that and realized that she needed to do something about the truth of the curse as well.
Before she was overcome by arousal she squeaked, “And after you’ve given yourself a blow job, you’ll know the truth about my curse.”
“That’s really gross!” Left Jess replied.
Jen ignored her, “Also, watching me masturbate won’t bother you... You’ll even help out.”
“Jen this is making me uncomfortable.” Right Jess added.
“Um... Remember that increased libido problem I have?” Jess added, only half paying attention to her sister as she reached towards her wet groin.
“I’m about to burst over here.”
“I get it Jen, you’re an excessively horny pervert...” Jess continued.
“What about the dare?”
Jen hated how her sister treated it as normal. The words felt wrong, but she was at her tipping point. She let out a sexual moan and shouted, “I dare you to give your cock a blow job with your other head.”
Jen finished and watched as her sister’s left head stuck out her tongue. In moments, the tip swelled into the familiar shape of a cock, then developed a small hole in the end. The pinkish skin blended into the more tan shaft and became slightly wrinkly. Veins developed along the length as it finished forming. It hung flaccid a few inches from her mouth, dripping with saliva.
Left Jen let out a muffled, “Wha hha fuuck.”
After a few seconds the dick began to swell until it was erect.
Right Jess only had a enough time to say, “Oh my gosh!” Before wrapping her mouth around her twin head’s cock tongue.
It almost looked like her two heads were making out if not for the tube of flesh between their lips. Jen was too aroused by the sight to stop herself from shoving her hands into either groin. As Jess sucked her cock tongue, she knelt down in front of Jen. Without really looking, she gently pulled Jen’s hand out of her left groin and carefully removed her panties. Once her wet cunt was visible, Jess began to massaged Jen’s left clit. Both girls made embarrassing sounds as they were overcome with pleasure.
Since Jess had taken over Jen’s left pussy, she was free to use both hands on her right crotch. Soon, the groin that her sister was working on climaxed. Jen squirted hot fluid onto her sister’s hands, then heard her let out a loud moan. She looked up just as Jess’s left neck convulsed. As cum shot out of her tongue, her other cheeks puffed out. A moment later, the white fluid came dribbling from the sides of her right mouth. Jen continued to rub her right clit and soon reached a second orgasm.
She let out one more moan, then collapsed back onto the bed. Jess backed up and fell into the desk chair. She tipped her heads away and let the cock pop free with a quiet slurping sound. Her right head swallowed the cum while the left just looked vacantly at the ceiling. The cock slowly shrank.
After a minute, Jen caught her breath and sat back up.
“So do you believe me now?” She wheezed.
Jen’s right head answered, “Every word...”
“That Kyle bastard is going to pay for this...”