Disclaimer: I don't own Portal or Portal 2.

A/N: TheGirlWithTheOnyxRose, this is for you! :] I beat Portal 2 before playing Portal, but I believe in doing research when doing a fanfic, so I took the liberty of watching videos of Portal gameplay to find some funny quotes.

If Sherlock yelling at the telly over how impossible the physics were wasn't funny enough, John was howling by the time that GLaDOS started insulting him.

"The enrichment center regrets to inform you that this next test is impossible—"

"Nothing is impossible, you machine," Sherlock retorted

"Make no attempt to solve it," GLaDOS deadpanned.

The longer that it took him to solve it, the angrier that Sherlock got, mainly because GLaDOS was antagonizing him.

He was triumphant when he solved it.

"Fantastic. You remain resolute and resourceful in an atmosphere of extreme pessimism."

"Obviously."

When he got to the part in the game when he got the dual portal device, things really got interesting. Sherlock got through the chambers a lot quicker, and he genuinely started to enjoy playing the game. He thought that the game was a perfect stimulation for his mind when clients weren't rolling through their flat.

"You did it. The Weighted Companion Cube certainly brought you good luck,"

"Where would I be without my Companion Cube?"

"However, it cannot accompany you for the rest of the test and, unfortunately, must be euthanized."

"WHAT?"

"Please escort your companion to the Aperture Science Emergency Intelligence Incinerator."

"No, no, NOOO!"

Sherlock tried every possible solution to get his Companion Cube through the chamber to the next level without having to destroy it. Unfortunately, nothing worked and he begrudgingly threw the cube into the incinerator. For the next couple of chambers, he was fuming. He powered through the chambers as if he was trying to prove to GLaDOS that he wasn't a heartless or unintelligent player for having to kill his Companion Cube. This was especially true when he almost got incinerated. John was sitting on the couch next to him, eating a sandwich and reading the newspaper as if this was totally normal.

"Didn't we have some fun, though? Remember when the platform was sliding into the fire pit and I said, "Goodbye" and you were like, "No way!" and then I was all, "We pretended we were going to murder you?" That was great!" GLaDOS sounded way too pleased.

Sherlock snorted. "Please. You sound like Moriarty."

"You're not a good person. You know that, right?"

"You've told me many times before."

"Good people don't get up here."

"I'm not the nicest person, nor do I claim to be. So, I think I'm fine making my way up here."

John enjoyed the banter that Sherlock exchanged with GLaDOS. It reminded him of when he first started watching crap telly, yelling at the TV host. For someone so brilliant, it was really hilarious watching his best friend be snarky with something that can't even respond.

"This is your fault. It didn't have to be like this."

"I'm not kidding now. Turn back or I will kill you. I'm going to kill you. And all the cake is gone! You don't even care."

"I never was one for cake, but I'm sure Mycroft would be heartbroken over the thought of there being no cake."

The tea John was drinking ended up on the other side of the room. It was a pretty distance considering it was through his nose.

"Well, you found me. Congratulations. Was it worth it? Because despite your violent behavior, the only thing you've managed to break so far... is my heart. Maybe you could settle for that, and we'll just call it a day. I guess we both know that isn't going to happen. "

"I wasn't aware that AIs had hearts. However, you're vastly intelligent and your cunning nature is too much like a human. So, I'll give you that."

John didn't know why he was cheering Sherlock on like he was playing a game of football, but he did it anyway. Now he wanted to try the game for himself. He felt his skin crawl when GLaDOS's voice dropped into an almost seductive tone while she talked about murdering everyone in the facility with a deadly neurotoxin.

They both cheered when Sherlock finally beat her. When he finally got his cake at the end, he gave a "HA!" because the person who was supposedly in the chambers before him wasn't as smart as he was.

As a joke, John bought him a Black Forest Cake. Even though Sherlock said he wasn't a fan of cake, he couldn't resist cutting a slice for both of them and Mrs. Hudson. He sent a picture of it to Mycroft to taunt him since he was on a diet.