Unlike in the movie, part 1 ended with Marty being transported back to the present time. Part 2 picks up there where Marty discovers that some things have changed, then he travels to the future and back to the past like in the movie. All characters in the story are over 18 years of age.
"Wake up Marty."
Marty slowly opened his eyes. He was sitting in the front seat of a DeLorean, the same DeLorean that Doc Brown claimed to be a time machine. The last thing Marty remembered was going to the "Enchantment Under the Sea Dance" with his mother. Did he really fuck her in the back seat of a car? Maybe it was a dream.
"What happened, Doc?" Marty asked. "Did I really go back in time?"
"You did," Doc said with a stern look. "And you jeopardized the space-time continuum by your actions. Really Marty - sex with your own mother?"
"Well technically she wasn't my mother at the time," Marty said trying to downplay the incident. "But I still don't understand how I got here. I don't remember anything after getting out of the car with, uh, my mother. Dad was supposed to come and rescue her from me but he never showed. I guess they got together somehow or I wouldn't be here."
"From what I've been told," Doc explained, "Your dad clobbered Biff with a crowbar and then took your mother to the dance. I came looking for you when you didn't show at the agreed time. You were unconscious in the parking lot. I carried you to the DeLorean and sent you back before you could do any more damage. That was 25 years ago."
"Wow. Twenty-five years? For me it was just a few days ago. How long have I been gone from here since I went back in time? Has it also been a few days?
"I wish it was, Marty." Doc Brown replied. "I must have programmed the machine wrong before sending you back. You were supposed to return tomorrow, a few hours after you go back in time, to avoid creating a paradox. You are now here before you go back. We are in uncharted waters."
"What if I don't go back? Can't we just skip that part? That way everything will return to normal"
"It's not that easy, Marty. First I need to know what has changed since before you went back. For example, did you have a brother named Dave and a sister named Linda? Was your father a famous science fiction writer and your mother on the board at the country club? "
"Yes, Dave and Linda were my brother and sister, but my dad wasn't a science fiction writer. He was a real loser and my mom was a slut."
"Great Scott," Doc Brown exclaimed slapping his head. "This is a disaster, Marty. I need to know what else has changed. Take my car and look around, but be careful. The space-time continuum is very delicate now that you are back."
Marty drove to his house and immediately realized something was amiss. Biff was out front washing a car. When he left, his dad was washing Biff's car while Biff was inside fucking his mother. Marty parked and hid behind a tree to watch. An attractive girl came out of the house. It looked a lot like his sister Linda, but this girl wasn't chubby. She was beautiful with curves in all the right places.
"Hey Biff," he heard her say in a sexy voice. "Mom won't be home for another hour, Dave is with his butt fucking boyfriend, and Marty is over at Jennifer's house. Do you want to come inside?"
The girl pressed her body against Biff and rubbed her hand over the bulge in the front of his work pants. She stood on her tiptoes and kissed him on the neck. Marty stared at the skin tight material of her red shorts which molded suggestively to the contours of her shapely ass cheeks.
"Uh... look, Miss Linda," Biff stuttered, "We can't do this anymore. Last time your dad almost caught us. You know how much I need this job."
Marty couldn't believe what he was witnessing. This couldn't be the same arrogant bully who had fucked his mother right under the nose of his dad and certainly not the same bully he met when he went back in time.
"If you don't take me inside and fuck me right now then I'll tell Dad that you attacked me," Linda replied squatting in front of him and pulling down his zipper. "Or, if you would rather, I'll just give you a blowjob here and then you can fuck me over the hood of the car. I'm sure the neighbors would enjoy the show."
"Um... please Miss Linda," Biff said looking around to see if anyone was watching. "Not here. I... I'll go inside with you but you can't let your dad find out."
Well some things haven't changed, Marty thought. My sister may be better looking but she's still a slut, and Dave is still into guys. He watched the two of them go in the house. He hadn't noticed the car that pulled up to the curb behind him or the woman who had climbed out of the car.
"Hello Marty. Guess who's home?"
He turned and found himself staring at a pretty redhead. She looked to be in her early twenties and strongly resembled his mother from the past only this woman was more endowed in the chest. Her white blouse stretched across a pair of ample tits. The short skirt she was wearing clung tightly to her body.
"Uh..." Marty fumbled to find the right words.
"Is that any way to greet your Aunt Jill? I know I wasn't supposed to get here until tomorrow but John's on a business trip so I decided to come early."
Marty never had an Aunt Jill. In fact, she was much too young to be his aunt, but he had to admit that the resemblance to his mother was remarkable. She came closer and gave him a big hug, pressing her tits suggestively against his chest.
"Marty, don't just stand there looking like you've never seen me. Be a gentleman and carry my bag inside."
Marty realized that it would be a disaster to go inside while Biff was fucking Linda.
"Um, look," Marty said. "I promised my girlfriend Jennifer that I would come over this afternoon and I'm really late. I was wondering if maybe you could you give me a ride."
"Are you still fucking that slut?" Jill laughed. "She can wait. I didn't come all this way just to have you run off to your little whore."
"Yeah but... well, Linda is in there with a boy," Marty stammered. "Maybe we shouldn't disturb them just yet if you know what I mean."
"Marty, why are you acting so strange? We both know Linda will fuck anyone wearing a pair of pants... and a skirt too from what I understand. Now quit stalling and carry my suitcase inside."
Marty, still unsure with whom he was talking, reluctantly grabbed the suitcase and followed Jill into the house. As they headed down the hall they could hear loud moans and squeals coming from behind a closed bedroom door.
"Fuck me Biff... harder... shove you big cock up my tight cunt... uuunnnnggghhhh... yes... oh fuck... AAAAAHHHHHHHHHH..."
"So Linda has a new fuck toy," Jill laughed. "I don't blame her. Biff has a very nice package. Believe me, I know!"
Marty followed her into what was Dave's bedroom. She acted like it was hers. Marty put down the suitcase and tried to leave but Jill grabbed his arm.
"Not so fast Marty," she said pulling him back into the room and pushing the door closed. "Just because I'm a married woman doesn't mean that I haven't missed my nephew."
She pushed him onto the bed and began unbuttoning her blouse. Marty sat there wide-eyed wondering what happened to his family since he went back in time. After removing her blouse, Jill reached back to unsnap her bra. Two magnificent round and firm breasts bounced onto her chest. They were capped with dark pink areolas. Eraser-sized tips poked slightly upward from her swollen nipples.
"I'll bet you've missed these, Marty. I know they've missed you."
Marty mumbled something unintelligible. Jill smiled and held the two nicely shaped melons in her hands gently squeezing the soft tissue. She rolled her thumbs across the hard nipples.
"Is your cock getting hard, Marty?"
It was. Jill dropped to her knees in front of him and unfastened his jeans. She pulled them down his thighs along with his briefs. His hard cock sprung free. All seven inches poked up from his lap and wavered back and forth. Jill bent over and swirled her tongue across the knob. After dousing it with spit she wrapped her fingers around his shaft and slowly stroked his hard flesh. Her huge tits jiggled back and forth on her chest.
"That's more like the Marty I know."
Looking up into his eyes Jill slid her lips over his swollen knob. After teasing it some more with her tongue she plunged her mouth down his length and bobbed her head up and down in a series of rapid sucking motions. She kept her fingers wrapped around the base of his shaft and stroked his cock while she fucked him with her mouth. Marty moaned and put his hands on the back of her head. He was seeing stars.
Jill pulled her drooling lips from his cock to catch her breath before slamming them back down his length. This time she took him into her throat. She held him deep and shoved her tongue out to lick his balls. Then she moved back to his knob stimulating the sensitive underside. Marty was about to lose it. Jill, sensing his impending release, pulled away at the last second and squeezed the load back into his balls.
"Not yet Marty," she giggled licking a trickle of cum off the tip of his cock. "Don't you want to fuck my titties first?"
Jill yanked the jeans off Marty's feet and pushed his knees apart. She slid between them and dangled her tits across his throbbing cock. She wrapped her hand around it and rubbed the slimy knob over one of her nipples. She did the same to the other nipple. Jill drooled a strand of spit from her mouth bathing his cock in saliva, then slid it between her tits and pressed them tightly around his hard shaft.
She rolled her huge globes back and forth across his hard flesh, then up and down his shaft. She bent her head down and flicked her tongue across his knob each time his cock punched up between her two beauties. Occasionally she dribbled spit onto his cock to keep it lubricated. Marty was seeing stars. Once again, Jill squeezed the base of his cock forcing his load of cum back into his balls.
Jill stood and lifted the hem of her short skirt. Marty found himself staring at a pair of thin pink panties that stretched tightly across her swollen pussy. A golf ball sized wet spot circled the opening.
