Carl Tennyson, father to Ben Tennyson, uncle to Gwen Tennyson, opened his front door and was greeted by his son’s bouncy and well-formed girlfriend Lucy. His fifteen-year-old son had been dating Lucy for just over a year now. Carl wouldn’t tell Ben, but he was happy he had a girlfriend. Up until meeting Lucy, he seemed to show no interest in any other girls. As far as Carl knew, up until Ben started dating Lucy, the closest thing Ben had to a girlfriend was his cousin Gwen.

“Hello Mr. Tennyson, how are you today?” Lucy politely greeted with a big grin. Lucy had more about her that was big other then her smile. She was a pudgy brunette, who instead of being ashamed of her full figure embraced it without fear. She wore tight clothes and short dresses that barely covered her legs. Carl was too old and married, but if he was single and fifteen, he would of loved to get to know the plump girl better.

“I’m fine Lucy, Ben’s upstairs waiting for you. I’m heading out and won’t be home until late, you be good,” Carl said as he got his coat on. He knew what was going to happen the minute he left, Ben and Lucy would start going at it right away. Carl knew his son was sexually active and wasn’t going to bother him about it. What he wanted to do with the chubby but adorable Lucy was no business of his.

Before leaving, Carl remembered his sister had said Gwen might be stopping by later. “Lucy, Ben’s cousin might be stopping by later on. I don’t think you’ve met her before, her names Gwen. So could you and Ben try to stay…decent until she arrives?”

“I’ll try Mr. Tennyson,” Lucy told Carl who nodded back. As he left the house, he hoped Lucy listened to him and kept her clothes on. Gwen was a bit of a prude and if she arrived at his house to find Ben naked with another girl, she was going to flip. Gwen was so reserved; she really needed a boyfriend to help her relax.

The second the door closed behind Carl, Lucy raced up the stairs. Her big, fat breasts bouncing as she rushed towards Ben’s room. She hadn’t seen Ben all day at school and was in desperate need of some good loving from her boyfriend. No one screwed her as well as Ben, not that she had been with any boy other then Ben. Lucy had one man in her life and that was Ben. He was her true love and she just knew they were destined to be together forever.

Rushing into his room without knocking, Lucy stopped dead in her tracks at the sight of Ben half naked on his bed with a tiny green alien clinging to his shaft. Ben had his head back as the tiny woman on his cock, rubbed her small, but supple body all over his shaft. She was all over Ben’s cock, licking the precum from the head before running her tongue down the side. She was less then half the size of Ben’s manhood, but that didn’t stop her from pleasing her giant master.

“What are you doing?!” Lucy demanded, breaking up the full body handjob. Ben opened his eyes and stared at Lucy mutely not sure what to tell her. Lucy stared back, tapping her foot furiously waiting for an answer. Finally, Ben answered in an informal way.

“Just warming up for you, Gwen.”

“Ben Tennyson,” The girl Carl Tennyson knew as Lucy said as she strutted over to Ben. With a snap of her fingers, the pudgy Lucy disappeared and in her place was an equally pudgy redhead that Ben knew very well. As the illusion faded, so did her clothes. The naked redhead smirked at her lover of five years and hopped on the bed with him. “Next time, wait for me. You know I love warming you up.”

They kissed passionately, a brief but heated kiss to greet each other after a hard day at school. After coming back from space, Gwen had resumed their relationship in secret, keeping everyone in the dark including their own parents. It had been hard at times to hide their love for each other, but under the guise of being best friends they managed to keep it under control. As the years went by, Ben and Gwen’s love didn’t wane. However, as they both became teens, people started questioning why two cute kids weren’t dating and why they spent so much time together. Desperate to keep their relationship secret, Gwen created a new identity for herself. It was hard at first to balance the two identities, but it was worth it to be able to go out in public and be with Ben without being frowned at. To be with Ben, no price was too high to pay.

“It’s nice to see you again, Mistress Gwen,” Shelina piped up from on top Ben’s crotch. The tiny alien was hanging on with one hand from Ben’s massive pole, waving happily up to her other master.

Smiling at the only person that she wouldn’t kill for being within a foot of Ben’s cock, Gwen scooped the tiny alien off Ben’s penis. Gwen lifted Shelina to her face, breathing in the musky smell of semen that lingered on Shelina. She gave the tiny alien a kiss, which covered her whole head. “I think I missed you most of all today. Class just isn’t fun without you inside me.”

“Thank you,” Shelina giggled girlishly. As Ben and Gwen became closer, so to did they become closer to Shelina. Being the only one that knew about them, Ben and Gwen shared everything with her, including their bed. Shelina was there best friend and whenever they had sex, she was always close by. One of the reasons for her closeness was the fact that Shelina lived both inside Gwen and Ben. The size-changing alien moved between the two teens, living in Ben’s scrotum one week, Gwen’s rectum the next and then switching between both their stomachs. Shelina loved living inside her benevolent masters. Never tiring of being close to either one at all times.

“Enough talking, I got homework so we better get this over with,” Ben told his two lovers impatiently. Ben had matured a lot over the years. Gone was the impulsive boy who jumped into everything without a second thought. His relationship with Gwen had played a part in making him grow up. It makes a person mature when they have to hide a relationship from the world. Even still, when it came to sex, he was still ten.

“Romantic isn’t he?” Gwen sardonically asked Shelina who nodded gently. Gwen narrowed her eyes at Ben, who was anxiously holding his throbbing cock for some good old fashion banging. Gwen’s pussy dripped at the thought of having his big hard cock inside her again, but Gwen decided she wanted something else. Grinning impishly at Ben, she crawled towards him on the bed. Moving slyly for someone whose body was so round and fat.

“Actually, I was thinking about something else. We’ve been just fucking for a month now, I don’t want to have too much of a good thing so maybe it’s time we spice things up,” Gwen chuckled wickedly.

Ben’s eyes widened, he knew what Gwen meant by spicing things up. They hadn’t just been fucking this last five years, they had also been experimenting with both Gwen’s magic and his Omnitrix.

Gwen had fucked each of his aliens, even the putrid Stinkfly, who surprisingly had a very big cock. She had also tried everything else with the alien’s forms of Ben, including at the suggestion of Shelina, the many tongues of Upchuck. Gwen shivered at the memory of being swallowed by Wildmutts enormous cock and then released when Ben screwed an amazing sized Shelina. Being inside Ben had been such a rush for Gwen; it made her realize how much enjoyment Ben had gotten from being inside her.

There fun was not only limited to the Omnitrix. Gwen had learned a vast number of spells that did everything from make her fatter to multiplying her body. Ben was still suffering from dehydration from the orgy he had with five very horny fat Gwens. Gwen did everything with Ben, stuffing him down every hole and enjoying his movements for as long as she pleased. There was an unsaid rule between the couple; When Gwen was in the mood for something different, Ben had no say in what she could do to him.

“Oh boy, bring on the show,” Shelina cheered on from inside a fatty fold on Gwen’s side. When not inside the couple’s body, she loved to wallow in the fatty folds of Gwen’s enhanced form. It was safe enough inside Gwen’s folds and it gave her a good seat to watch the action.

“Let's spread out on the bed,” Gwen ordered Ben to do. Sighing and wondering what his sex addicted cousin had in store for him, Ben did as he was told. His cock remained hard, even with the possible craziness in front of him, he knew he’d somehow get off. If Gwen used him to scrub her fatty folds, he would get off. If she used her magic to turn him into a tampon, he would get off. If she just farted on him for an hour without touching him, he would get off from that too. What was there to say, Gwen drove him mad with lust no matter what she did.

“Oh yeah baby, I feel it coming,” Gwen muttered as she stood in front of the flat boy. Ben looked down to see what Gwen was doing and saw her clutching her ass halves as they grew in her hands. He had seen her do it a hundred times, but never did Ben get sick of watching his cousin’s ass expand. He licked his lips as Gwen’s normal bubble butt swelled out like it was filling with air. Each cheek bounced as it inflated, growing until it was bigger then Gwen. It was like seeing someone carry two huge globes on their back, they dragged as Gwen lifted herself on to the bed next to Ben. Gwen stood over Ben, starting to turn around to drop her gigantic keister on top of the willing and able boy.

“You’re going to bury me under you ass?” Ben asked with a tiny bit of confusion over the mundane deed. It wasn’t that being buried under a giant ass wasn’t exciting, but Gwen usually came up with more perverted games to play with him. This was tame compared to a few weeks ago when she shrunk him down, attached him to her clit and used him as cock to fuck Shelina all night long.

“Sure why not? If I remember correctly, the first sexual thing I ever did to you was burry you under this very ass. Remember back then when you thought girls had cooties and I thought burps and farts were gross?”

Ben nodded, remembering all the way back when he thought his cousin was a dork instead of the sexist girl alive. Those had been strange times and he wasn’t sure what would have happened if Gwen hadn’t sat on him all those years ago. The light started to disappear and Shelina saw Gwen bending over to put the full weight of her ass on top of Ben. Open mouth and hands up, Ben greeted the mountain of blubbery fat with a lick, making Gwen moan. Gwen pressed her colossal ass down, burying her cousin under her fanny. She moaned and groaned as she felt Ben clawing at her cheeks, not trying to escape, but instead pulling the ass halves apart to reach her puckered anus. Just sitting there, she enjoyed the frenzy going on under her, amazed that after all these years Ben’s libido was growing stronger.

Things were never certain in life, but Gwen knew her future would involve some certain things. She’d always have Shelina, offering a shoulder to lean on and an extra pair of hands to grope her. She’d always have her fat, jiggling all over the place and making the boys drool. And she’d always have Ben, fucking and loving her. Like their lust, the love between them would never, ever run out. Even if the future brought new enemies or old ones, they would be together. Facing it as family, friends and lovers.