Three years after meeting with his father, thirteen year-old Phineas Flynn was working in the backyard on another Summer's afternoon. Mr and Mrs. Flynn-Fletcher were gone for the week to an antique's convention leaving 20 year-old, grown up Ferb in charge. Ferb, however, agreed to letting Candace have domestic conquest while he and Phineas worked steadily at their projects outside. Phineas' girlfriend, Isabella, then came into the yard with Buford and Baljeet following behind.

"Hey Phineas! Whatcha dooin?", she asked, cute as ever.

"Oh hey Isabella! You guys are just in time! Ferb and I were watching a movie the other night, right? It was a mix of all your stereotypical monsters in one, slightly comical adventure. Y'know, vampires, werewolves, Frankenstein creature, and that sorta stuff? Well then Ferb and I came up with the idea of making a machine that could transform you INTO those sorts of things and everything else if you wanna! Won't develop the mind-set of course, but you could turn into a were-wolf at the full moon or hide from the sun as a vampire. Want in?"

"Duh!", Isabella smiled, picking up a screwdriver.

"Well it's not like we have much lives. What the heck?", Buford joked, pitching in.

As everyone worked, Perry walked by through the yard then, rolling his eyes as he heard Candace blather on about his fur shedding on the carpet.

"'Blah blah blah blah blah.'", Perry mimicked as he pulled out his hat. "Ferb, were you sure it was a good idea to let CANDACE rule the house?"

Ferb smiled and gave a nod.

"You're crazy. Anyway Phineas, I'm off to punch your dad in the face.", he said casually.

"Tell him I said hi!", Phineas smiled. "Oh and Perry?"

"I'll let him know the coast is clear tomorrow.", Perry nodded before getting into the tree and disappearing.

One day, every month, the cameras would be replaced in the yard. One day, every month, Perry would take them down and continue to fool Monogram how the secret was blown. Three years at it and everyone was used to this routine though no adult was any wiser. Heinz, in the meantime, reserved being evil. He would build inators, pretending to blow up City Hall, but he didn't really do anything that desired a conquer to rule over anything. When he wanted to see Phineas, he would sneak off, saying he was going somewhere such as to the grocery store or to the park for ideas. Once out of the camera infested area, he would visit. Even during the holidays, excuses were made for them to quietly and discreetly get together and have their own personal fun.

But as things progressed with Phineas and everyone, the machine was halfway through being built when Ferb paused to look over the blueprints. After seeing what part everyone else was doing, something caught him. He looked at the prints, looked at Phineas, then back at the prints. He looked back up again, his eyebrows furled together in confusion when it suddenly came true in his mind.

"P-Phineas-!", he started to say when the machine suddenly began to act up.

Sparks flew, it shook and the ground quaked as well. As everyone else backed up, Phineas was slower, wondering what was wrong. Suddenly there was a bright flash and everyone shut their eyes tightly to avoid being blinded.

When the light died down, they looked again and gasped in shock. Phineas finally felt his arms lower from his face and looked around. Everyone was safe, though they seemed surprised. Ferb was looking the most surprised, and actually somewhat scared by his ghostly white face as he stared at Phineas. For a while, Phineas was confused about this. Was there something on his face? They looked like he was turned into a zombie.

"Ph...Phineas?", Isabella asked, turning slightly green as she stared at him.

"Yes?", he asked, nearly choking on his own voice when he heard it.

It was much higher. It was softer too. It certainly wasn't his. He ran a finger through his hair, wondering how that happened when he noticed something else. His hair was much longer than before. Finally daring himself to, Phineas looked down at his body.

"AAH!", Phineas screamed as he saw it was for a she.

Everyone had to cover their ears in literal pain as Phineas' new pitch reached past Candace's.

"WHAT ON EARTH HAPPENED?", she asked wildly as she looked about her friends. "I'm a-a-a GIRL! Did the machine do this? Oh my gosh I'm a girl! Wh-what's Mom and Dad going to say when they see me like this, Ferb? What's MY dad going to say?"

"I'm not sure, but as I was about to say, you turned up the voltage to high. It over-powered the machine and made you a girl, apparently.", Ferb said, backing as Phineas stepped closer when she talked.

Phineas wanted to double check to ensure this was PHINEAS' body but doing so, she quickly pulled her hands away, knowing good and well not to really touch lower than the collar bone. Her clothes even changed. From the yellow and orange striped t-shirt with blue jeans, she was now wearing a yellow and orange-striped blouse with a blue denim skirt. Even the tennis shoes were now something girlier looking with the hearts sewn into it.

"Um... Phineas?", Isabella asked, just now noticing something far too embarrassing for any girl to say in public.

Phineas looked up, curious why she was blushing when Isabella placed a hand below her own collar bone. Looking again, Phineas quickly blushed just as fast and covered her chest. Her shirt may have changed into a girl's shirt but there wasn't anything underneath to change into girl's clothing as well.

"I-I think I might have something for you.", Isabella said, coming over and pulling Phineas out of the yard with her.

At Isabella's bedroom, Phineas sat on the bed as Izzy rummaged through her dressers. The shirt was taken off but Phineas kept covered with her arms as she waited. They have been dating for three years and not once was there a more embarrassing and awkward situation than then. And try being accidentally locked into a tiny closet together and later on discovered after Phineas had tripped on top of Isabella after trying to rearrange themselves into a more comfortable position.

'I had a feeling this sorta position would be happening by the time we were older and had been married, but I never thought I'd have to be like this!', Phineas groaned in her mind as she waited patiently.

Finally she was properly dressed and they returned to the backyard. But as the boys were already working on the machine to turn Phineas back into a boy, Candace called to the yard for Dinner and time was finally noticed.

"Shoot.. It IS dinner time.", Buford remarked.

"Guess we will just have to work on this tomorrow.", Baljeet shrugged.

"Guess so...", Phineas sighed.

"Sorry Phineas.", Isabella said. "At least it'll only last till tomorrow."

"Yeah. Later, Isabella."

"Later.", she leaned forward to kiss her boyfriend but they both suddenly remembered the situation.

After a moment of confusion, they settled for a hug and went their ways. Phineas and Ferb walked back inside at the same time as Perry stepped through the pet door at the front. Perry took one look at Phineas and instantly knew what had happened.

"KRRRRRR!", the platypus exclaimed, jumping back. "'Phineas? What happened?'"

"Oh! Th-there you are Perry!", the girl tried to offer a weak smile but Perry had finally regained a bit of his senses.

"Wh-what-?", he stammered but was interrupted by Candace.

"Come on you guys! Dinner's gonna get-", the young woman stopped as she saw the trio, her eyes resting chiefly on the odd-one out.

"...N-now Candace! I know what you're thinking!", Phineas began frantically.

"I KNEW IT!", she suddenly exclaimed with a manically mischievous smile, pointing at her sister. "I KNEW you two would get into trouble! HA! What? Did the invention disappear? Is it finally gone? WHOO! FINALLY! A boy will FINALLY understand what us GIRLS have to go through! And when Dad gets here tomorrow you are SOOO busted! HA! Two birds at once! This is awesome!"

"The invention didn't disappear.", Ferb said, cutting in to the other's victory dance. "We're going to change Phineas back tomorrow. Maybe Mr. Doofenshmirtz won't mind helping us."

"Hopefully it would be BEFORE Dad gets here...", Phineas inputted. "I don't know about you two but I'm like, DIEING to get back to normal."

"NO!", Candace's smile fell. "No you GOTTA be a girl! At least for a little while longer! Phineas! You know how girls and boys are always fighting and the girl finally says, 'you just don't get it'? YOU can help bridge that gap! You'd be a hero! Do you know how LONG girls have been waiting for someone to finally help make boys understand?"

"NO he won't!", Ferb said scowling at her. "Candace! I am NOT going to just sit back and let Phineas be used like that! I NEED a brother. I had to put up with you for the last 8 years. I'm NOT gonna put up with TWO of you! AGAIN."

The sudden action surprised everyone but Candace was quick to retort.

"JUST for tomorrow! It's not gonna be FOREVER! DUH.", Candace rolled her eyes. "Just let Phineas get busted at least!"

"Candace. I'M the eldest. You're under MY rules till Mom and Dad, MY dad, get back!", Ferb said.

"Uh y-yeah. I don't exactly wanna be a girl for very long. I don't even wanna THINK about using the bathroom.", Phineas shuddered.

"But-!"

"NO.", Ferb was determined.

"But-!"

"NO!", Perry insisted. "I'M the greater authority here!"

"But-!"

"Candace..", Phineas interrupted.

Candace looked over and saw her little sister pouting. Tears were welding up in her large blue eyes as she innocently gazed up back at her.

"Can we please not argue this?", she asked softly and cutely.

There's hardly anything that works better on 18 year-old girls than something that's drop-dead cute. Kittens are perfect examples of such things and that's what Phineas was being to her. An endearing little red bundle of fur. Unable to fight it, Candace pouted and agreed. They sat down to their dinner, got ready for bed, and went to sleep. Perry agreed to staying with Ferb for the night, trying to be polite for Phineas' sake. It took Phineas a while as she tossed and turned in her bed. Her stomach ached painfully since after dinner and after finally twisting her legs tightly around one another, she found comfort and fell asleep.

BWA HA HA HA HA HA! For the boys who DARED to read this, raise your hand if you understand Ferb's point of view. For the girls who read this, raise your hand if you agree with Candace's point of view. For those who might ask, yes. Ferb is now a bit taller than Candace who's about Linda's height.

Boys who are persistent on reading, be fairly warned. This next chapter is going to get pretty blushy.