While Matt and Katie were thinking what to do, Riley came over to them.
"Hey, want to go take a walk on the beach?" she asked.
"Sure! Sounds like fun." Matt said.
Riley nodded and left, while Matt and Katie left to their room to get changed. Katie put on a light blue bikini, and Matt put on some green swimming trunks. But when Matt came out of the bathroom from changing, Katie noticed a considerable bulge.
"Oh... you're well endowed, aren't you?" Katie commented.
"Uh... yeah..." Matt responded.
"So that's why Riley seems so fixated on you, isn't it?"
"Yeah, she has known for some time. Back in gym class, my... manhood was the biggest one in our freshman class at high school."
"Huh. Speaking of gym class, it was weird that Riley's parents paid a lot of money so Riley could take a freshman gym class, even though she was still in 8th grade."
"Yeah, well, anyways, my locker is near the corner of the room. At the corner, there is a crack in the wall. I guess behind the wall was an unused supply closet that hasn't been used in a long time. But one day, I think Riley went in there to look through the crack." Matt said.
"You're telling me Riley wanted to be put into a high school gym class so she could see which boy had the biggest cock?" Katie responded.
"Well... yeah. So, that day, I had taken off most of my clothes while changing, so I was only in my boxers. I had a sexy looking picture of you in my locker, and since I was in the corner, I let my manhood get erect. Riley must've seen this, because I heard a slight gasp. Later that day, I questioned her about it, and she confessed. Whenever I see her, she now has a smirk on her face." Matt said.
"Well, considering her sex drive, she might try anything to get at your cock..." Katie said.
"Yeah..." Matt responded.
The two grabbed some things and left to the hotel entrance, where Riley was waiting. Riley had a black microkini on that barely covered her nipples, showing off her chest. She had her phone with her. The three then left, and walked upon the beach for a while, until Riley spotted something in the forest alongside the beach.
"Hey, look! A building! Let's go check it out!" Riley said.
"That's weird. The map said the only buildings on the island were the resort facilities..." Matt said.
The three headed towards the building. It looked like an old concrete bunker, and with all the trees, it would've been easy to miss unless you knew what you were looking for. Katie opened the front door, and looked inside. The inside was abandoned, but there was a suspicous staircase.
"Perhaps we should have one of us check out downstairs..." Katie said.
"Why don't you go, Katie?" Riley said a little too enthusiactically.
"Uhh, no. I don't trust you around my boyfriend. Matt, why don't you go check it out." Katie said.
"Sure." Matt said.
The girls started to talk, while Matt headed downstairs. In the basement there wasn't much, but Matt noticed, besides a small rock on the ground and a big heavy crate, two pink portals, one on the left wall and one on the right. They were not opposite each other. However, one was bigger than the other, and there were what looked like control panels on the sides. Matt grabbed the small rock, which was the size of the palm of his hand, and tossed it into the smaller portal. It came out the other portal, but now it was the size of Matt's head! Matt then decided to go into the smaller portal. When he came out the bigger portal, he was 10 feet tall! Amazed at his new size, Matt grabbed the large crate and lifted it with relative ease. Matt headed back into the larger portal and returned to normal. Matt experimented with the buttons on the control panel, and discovered that they changed the size of the portals. Grinning, Matt got an idea.
Matt took off his swimming trunks, and then changed the size of the bigger portal so it was slightly bigger than the other one. Matt stepped into the smaller one, and came out 7 feet tall! Matt put his swimming trunks back on, but now they were obviously two small now, and Matt had a larger bulge than before. Matt was curious about something else, though.
He found a stick inside the crate, and then put it partially into the smaller portal, and then pressed a button. The stick was now suspended in the portal. Pressing some more buttons, Matt changed the smaller portal's size so it was larger. Matt grabbed the stick, and then pressed a button. When he pulled the stick out of the portal, the half that had gone through the portal was now larger than the other half! Matt got a smile on his face as he got another idea.
Matt changed the size of the smaller portal, until it was only around as wide as his leg. Matt took off his swimming trunks, and then pictured in his mind Katie wearing Riley's microkini, which caused him to go hard. Matt looked at his cock; it was 8 inches long, and his balls were as big as eggs. Matt then stuck his rod and balls into the smaller portal. But Matt had forgotten to change the size of the larger portal, so because his cock filled up most of the space in the smaller portal, it did the same with the larger portal. A monstrously sized cock came out of the larger portal and smashed into the other wall, shaking the building.
"Matt! Are you okay?" Katie shouted with worry.
"Yeah, I'm fine. It must've been an earthquake or something." Matt shouted back.
Looking at the wall where his cock had hit, Matt noticed some cracks. This made Matt feel sexually powerful; his cock was so huge that it could crack cement and shake buildings! But coming back to his senses, Matt took his cock out if the portal and made the larger portal much smaller. He then out his cock and balls back into the portal, and then pressed a button to suspend it in place. He changed the size of his side of the portal so it was decently bigger, and then pressed another button. When he pulled his cock out, it was much heavier than he expected. Looking at it, Matt saw that his cock was now a foot long, with balls the size of tennis balls. Smirking, Matt waited until his cock went soft, which was about 6 inches long, and put his swimming trunks on. Matt was happy that his swimming trunks looked like they were about to tear, just from his bulge! Matt then decided to head upstairs.
Katie had been scolding Riley about trying to flirt and/or be sexual with her boyfriend when Matt came up. Katie was about to ask him what he had seen when she saw he was much bigger. Matt looked like a titan towering over the two girls!
"Matt! What happened to you?" Katie asked worriedly.
"Huh? What do you mean?" Matt responded.
"You're a giant! Something happened to you!" Katie said.
"And your cock looks even bigger than before!" Riley said.
"Okay, I'm just joking. I found this awesome thing downstairs! Let me show you!" Matt said.
Matt showed the two girls the portals, and explained everything he had found out. However, Riley had a smirk on her face. Holding up her phone, she took a picture of the enlarged Matt.
"Alright, Matt, you're going to do as I say or else I'll tell your parents what you have been doing!" Riley said.
"Are you blackmailing me?" Matt said, shocked.
"Well, I wouldn't call it 'blackmail'. You'll enjoy this." Riley said.
Riley then pressed some buttons, and made the larger portal wide enough that she could've crawled through.
"Okay, Matt, take off your swimming trunks and stick your cock in the smaller portal!" Riley said.
Matt didn't do anything at first, but when Riley started to enter his parents' phone number, he just sighed and did as she asked. When his cock came out of the larger portal, it was bigger than Riley! Katie just looked shocked. Riley started caressing the giant cock in front of her, and Matt couldn't help but go hard. After that Riley jumped on top of Matt's cock and started rocking up and down on it. Matt was having some difficulty controlling himself; to him, his cock was large enough that it was bigger than a girl. After a few minutes of this, Riley got off.
"Now, wasn't that fun?" Riley asked.
Riley then told Matt to take his cock out of the portal, and then Riley fiddled with the sizes of the portals. Giddy, Riley took off her bikini top, not revealing much more except her nipples. She stuck her breasts in the portal, and then pressed a button, and that suspended her breasts in the portal. She increased the size of the portal on her size, and then released her breasts. Her breasts were now huge, bigger than her head! But Riley wasn't done quite yet. She took off her bikini bottom, changed the sizes of the portals, and then hopped into the smaller portal. When she came out of the other one, she was taller than Katie, and Riley stood at 6 feet tall, and her boobs were close to the size of beachballs! Riley put her bikini top back on, but it barely covered her nipples, and covered almost none of her areola. She put on her bikini bottom, but it barely fit as well.
"Now, Matt, you and I are not going to shrink down. And if you tell my parents about this, I'll tell them I've just had a growth spurt." Riley said.
"What will your older sister Cynthia say when you get back to the hotel?" Katie asked.
"I'll tell her the same thing. And I could blackmail her, too." Riley said.
What happened next?
Choices:
1. The three go back to the hotel > (not done yet)
2. Riley wants Matt to be bigger > (not done yet)
3. Riley wants to be bigger > (not done yet)
4. After Matt and Riley leave, Katie makes herself bigger > (not done yet)
Giantess World
Author's Chapter Notes:
Previous Chapter: Chapter 1