I'm sorry if it's a little short, but I hope you'll like it anyway.

Alternate ending

Ben moved Gwen's hands to his cock, ordering him to help him cum by jerking him off as she sucked. Gwen obeyed, gripping Ben's cock, needing to use both hands as she couldn't fit her whole hand around Cannonbolt's thick rod, and stroking him as she sucked his balls harder.

After another few minutes, Ben let out a loud groan, firing several ropes of thick, hot cum into Gwen's hair and ordering her to rub it in like it were shampoo. Reluctantly, Gwen obeyed, getting Ben stiff again as he chose his transformation.

Gwen whimpered when she saw that he had chosen Ditto, but she didn't understand just how bad her situation was just yet. Ben used Ditto's powers to multiplies until there were seven in total, then they all pressed their Omnitrix, all transforming back into Ben, seven Bens in total.

Then, to Gwen's horror, all seven chose a different alien to transform into. One became the Mummy, one Wildmutt, one Heatblast, one Fourarms, one Diamondhead, one Stinkfly, and one XLR8. The Mummy let out his wrappings, ensnaring Gwen and lifting her up, wrapping around her ankles and wrists to position them, holding her arms out in either direction and, after the Fourarms got between them, holding her legs with her feet pressed together.

The Diamondhead got beneath her, lining up his literally rock hard cock to her ass as the Fourarms lined up both cocks to her pussy at one. The Wildmutt positioned himself so his cock was right in front of her mouth, the XLR8 and Heatblast standing on their side, the Mummy's bindings forcing her to grip their cocks with her hands, and the Stinkfly using his flight to line up to her bound feet.

On the Mummy's cue, all of them thrust at once, the Diamondhead and Fourarms forcing their cocks into Gwen so brutally she nearly went cross-eyed, not that she could scream, nor even breath with the Wildmutt knotting in her throat. Her hands both burned, one from friction from how fast the XLR8 was thrusting against her hand and the other just from the sheer heat from the Heatblast. Her feet were coated in slime before the Stinkfly even came, the natural slime of the Stinkfly coating her.

Gwen struggled as she always did of course, but as the aliens all kept going, getting rougher and rougher as they tried to break their record for who could cum the fastest and the most times as they changed positions, moving her around so all of them could get to try every part of her at least once, she realized that it was hopeless, there was nothing she could do. She would be Ben's whore for the rest of her life no matter what she did.

And with no way to change that, Gwen was left with nothing but the choice to accept it. Ben didn't notice it at first, not until they all returned back to Ben form to rape her like that. It was then that they noticed Gwen smiling, sucking whoever was in her mouth enthusiastically and moaning, actually, genuinely moaning as Ben fucked her on all angles.

Gwen no longer existed, not really. She was broken, scattered to pieces that would never be put back together. She smiled, spreading her legs and wondering aloud, "I wonder how many Ben cocks my tiny ass can fit at once~"

As it happened, she could fit three of the Bens' cocks inside of her ass at once, moaning at the top of her lungs as they pumped into her, making her bounce hard on their rods as she reached out, gripping two of the Bens' cocks and jerking them both off towards her chest as she tilted her head back and opened her mouth wide for the remaining to Bens to fuck her throat together.

They kept going like this for another hour, filling Gwen up in every hole several times, before Ben wanted to fuck her himself, as he was. The many Bens becoming Ditto, merging back together, and becoming a single Ben again.

"Go get washed up." He said, "We're gonna have some more fun today." Gwen smiled excitedly, hurrying inside to shower.

Gwen dropped to her knees and took his member out before he even ordered her to. She didn't take it into her mouth though, rubbing it against her face and looking up at him with puppy dog eyes, "Master, may I suck on your delicious cock please?" She asked hopefully.

"I don't know, I'm not sure you want it enough~" Ben teased, Gwen pouting, "I do Master, honest!" "Could you prove it? My balls need some attention to you know." Ben said, Gwen nodding, "Yes Master." She said, lowering her head and taking Ben's balls into her mouth, moaning at the feeling as she sucked on them.

Ben moaned, proud to have finally broken her. He stroked himself as she sucked harder on his balls, making him cum after a few minutes. Gwen began to rub it into her hair immediately, as she loved smelling like her Master's seed and hated that she had to shower the smell out every so often.

"I think you've earned it," Ben said, pressing his tip up against her lips. Gwen's eyes sparkled happily, "Thank you Master!" She said before engulfing his cock, swirling her tongue around it in worship as she bobbed her head up and down, loving every second as Ben grabbed her head and began to skull fuck her.

She could easily take his entire cock without gagging these days, but she gagged anyway because she knew Master enjoyed the feeling and sound of it. Ben groaned, fucking her throat harder for several more minutes before he came again, pumping his thick, hot seed down her throat.

Gwen diligently swallowed it all, looking up at Ben for approval. "Very good. Now, show me what you've got underneath those close~" He ordered, stepping back. Gwen nodded, standing up and slowly stripping down, showing that, beneath her bra and panties, her nipples she squeezed with clamps, and her pussy and ass were plugged with thick toys, the gentle buzzing of which could be heard now that she was naked.

Ben smirked, "Poor slut, do you know what you did wrong?" Gwen mocked a gasp, "I wasn't supposed to wear underwear underneath! I'm so sorry Master!" She said, "I should be punished~" She purred excitedly.

Ben smiled, "Yes you do. On your fours." Gwen assumed the position happily, placing her face to the dirt and raising her ass as high as it could go. Ben walked over, bringing his hand down hard on her exposed ass.

Gwen bit her lip, resisting the urge to moan for the first few strikes before she couldn't help it and began moaning steadily. After Gwen's ass had reddened deeply on both cheeks, Ben switched both the toys to their highest vibration setting and stepped back, turning into Wildvine and proceeding to lash and strike across Gwen's body, leaving deep marks across her legs and back.

Gwen came with a scream from the first of these strikes combined with the toys drilling her holes, and came again before he was finished. When Gwen's entire body, save for her face, was marked, Ben returned to his normal form and went over to her, removing the toy from her pussy and thrusting into her hard.

Gwen moaned, begging Ben to fuck her harder. Gwen's magic studies had found several spells for sex, including one that made sure Gwen was constantly as a virgin no matter how much she was stretched out, and one that prevented pregnancy unless Ben ordered it to do otherwise, making it safe for Ben to dump buckets of cum into her womb; not that he hadn't been doing so before she found the spell anyway.

Ben grunted and groaned, thrusting harder into her as he pushed the toy in her ass deeper inside her. He couldn't wait to test out all the other new sexy spells she had found, and even though summer was ending, XLR8's speed would let Ben visit Gwen anyway.

And she would always be more than happy to greet her master.