Author's Note: Hey! Kelsey here! This is basically a little one-shot on what I think should have happened after Isabella kissed Phineas in the movie, and Carl didn't hit them with the amnesia-inator. This is my first fanfic so go easy on me! Read & Review!

It starts from the part where Isabella asks Major Monogram the question… Sorry if the dialogue is not exactly the same as the movie.

Isabella raised her hand hesitantly. "Uh, Major Monogram?" Major Monogram acknowledged her, "Yes?"

"Just so we're clear… none of us would remember anything, right?" Isabella asked.

"Uh… yes," MM replied.

"Good!" Isabella said, looking slyly at Phineas. Immediately, she pulled him towards her and with a big "Muah!", she planted a kiss on his lips. It felt so good to finally kiss him!

Phineas gasped when they separated, then a smile grew on his face. "Isabella!" he exclaimed in delight.

"Hit it Carl!" Isabella exclaimed, feeling ridiculously happy.

Phineas saw Carl's thin finger coming closer to the red button, and immediately yelled, "Wait! Wait! Carl!"

Carl heard Phineas's desperate cries and stopped. "Sure, finish up whatever you have to do."

Phineas then turned to Isabella. "Isabella! Why did you kiss me?" He sounded both surprised and happy at the same time.

Isabella's cheeks flushed a beet red and she stared down at the ground, shuffling her right foot awkwardly. "Well…" She then looked up and stared into Phineas's blue eyes. "Because I like you Phineas! I've always liked you!"

"Oh." It was Phineas's turn to turn red. "Well, I like you too Isabella."

"Really?" Isabella felt a burst of happiness and she grabbed Phineas's hands and spun around. "Yes!"

"Pity we won't remember this." Phineas suddenly looked a little sad.

"Don't worry, I'll fix this!" Isabella turned to look at the others. "Guys, anyone has a ballpoint pen?"

Carl had one and passed it to the enthusiastic girl. Isabella gratefully took it and scribbled onto her hand, Kiss Phineas and tell him you like him AGAIN. She handed the pen back to Carl and told him, "Carl, now you can activate the amnesia-inator."

And Carl activated it.

The gang was then transported all the way back to Phineas and Ferb's backyard, where they stood there, bewildered, wondering what had just happened.

"What just happened?" Candace asked, looking around. She looked back at Phineas and Ferb. "I'm just surprised we're not here because of one of your inventions again."

Isabella noticed she was standing next to Phineas and felt a little giddy. Wiping her sweaty palms on her dress, she then noticed some smudged writing on it, reading, Kiss Phineas and tell him you like him AGAIN.

Isabella wondered what on earth had happened, and how that writing got there, but she didn't care. All she did was to grab Phineas and kiss him on the lips, and said, "I like you, Phineas Flynn!"

So that's it! Thanks for reading! Read & Review!