The next day, Matt and Katie's parents were shocked that they had grown again, but were mostly okay with it. Upon finding out that Matt was going to compete in the Mr. Olympia tournament, the town decided to have a complimentary outfit made for Matt that fit him pretty well, although it was only really a green speedo.
Fortunately for Matt and Katie, there was no school that day. Riley had invited them over to her house, claiming that she "wanted to show them something". Matt wore a bedsheet wrapped around his lower body, and Katie had one wrapped around her torso. Until they got new clothes, it would have to do.
Riley had told them to meet in her backyard, and soon the two met Riley there. However, Katie noticed something was different.
"Matt, wasn't I taller than you last time we met?" Katie asked.
"Yeah, but I found out that I tend to grow when I'm aroused or something..." Matt said.
"So that means your cock is even bigger?" Riley said delightedly.
"Uhh... yes?" Matt said, a little unsure on how to respond.
"That's amazing! Now, my parents and Cindy are out right now, and I haven't told Cynthia that you were coming." Riley said.
Cynthia was 6 feet tall, and she had large DD-Cup breasts, with a nice, curvy butt. She was 16, and had followed a similar growth pattern to Riley. And she was still growing, too. Cynthia also dyed her hair emerald green, giving her a very sexy look.
"By the way, I found out last night I had grown an inch since the last time I checked, so Cynthia believed my story! Anyways, come on in!" Riley said, leading to the two giant teens inside.
The back door connected with Riley's room for some reason, and when they entered, Matt and Katie could hear the shower being used, presumably by Cynthia. Riley told Matt to get on her bed, which he did, and the bed creaked a little.
"Okay, in order to show you what I wanted to show you, I need this rainbow colored rock I left outside. Katie, can you go look for it?" Riley said.
"Why didn't you get it beforehand?" Katie asked.
"I forgot I left it out there until you arrived." Riley said innocently.
Katie grumbled, then headed outside. Riley then jumped onto Matt's chest, and started to take off the bedsheet covering Matt's crotch.
"R-r-riley! What are you doing?" Matt asked uneasily.
"I wanted to see your enlarged monster under here! And I also wanted to see it grow! And, knowing you, you won't want to harm me, so as long as I'm sitting here, you can't do anything!" Riley said with a smirk.
"So that rainbow colored rock-?"
"Doesn't exist." Riley said, grabbing the tape measure near her bed, and measured Matt's cock, after taking off Matt's makeshift loincloth.
"A foot and two inches! But I'm sure you knew that already. Now, how to make you grow..." Riley said.
"Riley, where did you leave that towel?"
Cynthia walked into the doorway, completely nude and wet, her green hair glistening. At that moment, she realized what she was seeing that Riley had on her bed. To Matt, Cynthia looked like one of the sexiest girls on the planet, excluding Katie. When Matt saw her naked, his cock started to swell in between Riley's hands, slowly getting longer. Riley started to feel Matt grow beneath her, his muscles bulging and his body shifting. To Riley's delight, Matt's cock was growing thick enough that she was having trouble putting her hands around it! When it stopped, Riley measured it again.
"Wow, your cock is now a foot and five inches long, or seventeen inches! Thanks, Cynthia!" Riley said.
"Riley, once I can wrap my head around what just happened, we're going to have a serious talk!" Cynthia yelled. Then, with a less serious tone, "Uh, Matt, right? Can you call me later? Thanks!" Cynthia said, leaving the room, her breasts bouncing a lot, causing Matt's cock to swell a little more.
"Oh! It's now 18 inches! Wow, my sis really turns you on! I can't wait to be big enough to make you grow!"
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Connor Venten was observing a camera feed of both Matt and Katie.
"Ah, that Xtr-Growth-963 really is wonderful, isn't it? In addition to the growth properties of the last version, it causes males, especially their cocks, to grow larger when aroused. And when hit with a certain wavelength of light, a few minutes later the subject, male or female, grows again. Now, set up one of our machines to release a healthy dose of that light onto the girl, so that we know it works."
"Yes sir."
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Katie was starting to feel like Riley was lying about the rock. She felt an odd sensation, but she just ignored the sensation. She opened the back door and found Riley sitting on top of Matt, and Matt had a bigger cock than before.
"Riley! What have you been doing?" Katie yelled, annoyed.
"Well, first off, it wasn't sex. I'm still fully clothed, see? Oh, and thanks to Cynthia, Matt grew a bit more - especially his cock!" Riley said, rubbing Matt's cock.
"Really? Matt, stand up. I'd like to compare our heights." Katie said.
Giantess World
Author's Chapter Notes:
Matt may get some growth in this chapter, but don't worry, Katie gets some next chapter.
Chapter End Notes:
Katie gets some growth next chapter.
And in case you're wondering why I seem to cut my chapters short, it's because the device I use only allows me to input so many characters at a time.
And in case you're wondering why I seem to cut my chapters short, it's because the device I use only allows me to input so many characters at a time.