Kim discovered another side effect

By: Cheese111

"Oh wow, it's even better than expected." She crows cheerfully. Becky joins in on the odd smirk of your sister, sending a shiver down your spine. Without another word she beckons the group to follow her behind the house. In the backyard a massive tent had been set up and Kim was quick to explain her intent.

"You'll be staying in here for now, Becky. I've not yet isolated if your little growth spurt is capable of a second wind and I don't want to risk you hurting yourself by being inside our house when that happens. Also, you know, I'd like you not to demolish my home with your fat ass if you do." The two giggle loudly, the other boys sort of following along mindlessly. What has gotten into them?

"It'll be like a camping trip. Just me, little Willy and all of my boy-toys." Your girlfriend cooed with delight, giving you sly look.

"Hey! Don't talk about my friends like that." You snap back at her. They may have pushed themselves in to this situation, but you weren't going to let your sister and girlfriend be so disrespectful.

"Oh, I don't know. What do you say, guys? Are you my little toys to play with?" Becky put a seductive twinge in her voice.

"Yes." They answered in unison. Your head span faster than you thought possible as you looked your friends in the eye. What the fuck was that about? Had they planned this whilst you were gone to the bathroom at school or something? Kim noticed your exasperated expression and burst into giggles.

"Hahahaha, oh little Willy. Don't stress your head about it. Let's just say that along with being a bit taller, Becky's 'suffering' from a few added side effects. One of them is her musk. It's not gotten too much worse, but any man that takes a good whiff of it will be feeling helplessly drawn to do her bidding." Your jaw nearly hit the floor. But before you could begin to question the obvious exception, your sister spoke up again. "You're not affected because you've already been drenched in our fluids so much it's practically how you smell by default now."

Becky stood tall before you, a glint in her eyes telling you she was about to make things worse. "Here, let me demonstrate. Oh Blake, would you kindly get down on all fours and crawl to me like a dog?"

You were pushed aside as Blake didn't even hesitate to approach, going down on hands and knees to obey your girlfriend's command. She squatted down and gave him a pat on his head. "That's a good boy. You've earned your reward." She guided his head to her groin and rubbed it against herself. The stimulation felt great, making her stifle a moan. Though you were thoroughly disgusted by the humiliating display, at least you didn't have to wonder how your friends were so oblivious to her package when she literally rubbed their faces in it the first time.

It was as though the two girls had read your mind, as they were quick to step things up. "Well, I guess there's no need to be coy about this any more. Everyone, lose the clothes." Becky commanded cheerfully. You were horrified to see your friends so eager to obey, taking off their shirts and pants as quick as they could until all were as naked as the day they were born. Kim and Becky were eager to join them and your head nearly exploded as none of your friends seemed to give the slightest reaction to the revelation of their cocks. Not only were they completely okay with being outmatched by Kim and your girlfriend, they seemingly couldn't keep their eyes away from them, staring at Becky's groin. To nobody's surprise though, it was Becky who proved the horniest, her shaft already rising up to a fearsome two foot tall erection.

"C'mon little Willy, don't get shy now. Or do you need help?" She offered, prompting you to quickly shake your head and obey. The last thing you wanted to give those two was an excuse to punish you.