"Please don't touch that," groaned GLaDOS. "It's my old chassis, it's not some in kind of ridiculous fun house."
"Are you kidding?" enthused Chell, and she swung pieces of the android's former chassis around with glee. "It's like a big metal toy box!"
"You do realize that you're technically playing with my old corpse, right?"
"Eh, I play with your current body enough, it only seems fitting."
Chell had to duck to avoid the piece of debris hurled at her head.
Ever since GLaDOS had exchanged her former shell, the massive hanging cage complete with irritating personality cores, for her current one, a leggy synthetic android, she never knew... well, what to do with the old one. She lacked any emotional connection to it, and once the appropriate hardware and software had been transferred, it lacked any official purpose, so it just... sat there, in the massive decrepit test chamber she had stashed it in. GLaDOS had thrown it in there, hid the test chamber in the bowels of the Enrichment Center, and never thought about it again.
Until, of course, Chell had unearthed it. Stupid human.
"I still don't know why you don't want to keep this thing!" Chell was standing on top of the head, grinning with glee as it seemed to settle beneath her feet, until the android couldn't help but grinning herself.
"I'm glad you're enjoying yourself, but it doesn't have much point. Everything worth having in there is in here, and I thought you preferred this body?" GLaDOS placed her hands on her hips, and struck a pose for her human. And of course, Chell was so distracted she had to sit down. Cute. But predictable.
Chell's heart picked up it's paces as her eyes traced the curves of her android. The way she put her weight on her right leg, curving her waist along in to a delightful presentation, and way she cocked her hips to the side, could keep Chell busy for hours. She watched the way GLaDOS' jumpsuit pressed across her body, painting the contours of her calves and her incredible legs, and the way it pressed against her heaving chest and her mischievous grin, framed by her gorgeous locks of hair- Oh god, she's looking at me, she totally sees me checking her out.
Chell could only blush furiously as she pulled herself off of the chassis. "I... I wasn't checking you out, by the way."
"Oh, of course," GLaDOS grinned.
Before Chell could come up with some kind of biting response, she noticed something blinking red in the forgotten chassis. "Hey! What's that?"
"What's what? My old body? You mean the thing that you've been jumping on for the last ten minutes? Maybe you do have brain damage."
Chell reached inside, and after fishing around in the complicated net of wires and abandoned electronics, she yanked out the red light and the small electronic box that came along with it. "Do you recognize this?"
"Oh, you have got to be kidding me," GLaDOS frowned and stepped forward. "If that is even close to what I think it is, you should definitely not be touching that."
That was really the only incentive Chell needed. With a laugh, she found a small button on the box and lightly pressed it.
GLaDOS suddenly stopped mid-stride, and her face contorted in concentration, gasping and twitching in place. Her jaw went slack, and the AI tensed, before sighing and relaxing as she lowered herself to the ground.
"... Did... did that do what I think it did?"
GLaDOS' voice was slow and slurred, as a blissful smile lit up her face. "B- bliss. S'posed to generate bliss..."
Chell slid off the chassis with a thump, and swung her hips from side to side as she walked towards the prone android. GLaDOS was strewn across the light-dappled floor, resting on her elbows while her bent knees were held slightly apart in a statement of lazy arousal.
Suddenly, Chell realized what she was holding and broke out in a grin. "Oh. Oh. You mentioned testing euphoria, before, right? Some kind of... sub-system or something to make testing feel good? You... you built this little thing to trigger it,huh?"
GLaDOS' observed her lover with casual lust, which sent a thrill down her spine. "Yeah, I- ah! I guess I forgot to put that away..."
"So... what happens if I hit it again?" Chell shot a grin so wicked, it's parents should have sent it to military school.
The android shook her head, "No! Um. No, it would be... unnecessary, I don't think you need to-"
Chell hit the button again.
GLaDOS threw her head back and moaned, a gasping, shuddering moan that seemed to fill the entire space with sheer need. The android gripped the paneling beneath her as she shook, every nerve in her chassis completely over-ridden in a wave of pleasure that seemed to swallow her whole in it's wet grip-
"Wow. This is fun."
The AI breathed in short, shallow breaths as she tried to regain her composure. "I... I- mmm! I'm confiscating that thing when I'm done..."
"Say, I wonder..." Chell leaned down to her former tormentor with a grin, showing off a generous expanse of cleavage, as her fingers started to dance up GLaDOS's jumpsuit. She gripped the zipper by her collar bone, and started slowly dragging it down the android's body, savoring the feelings of her body underneath.
"What- what are you doing?"
"Hush. Science happening," Chell murmured. She made sure to keep the zipper from catching on any of GLaDOS' wonderful curves, which would have just ruined the mood. The zipper made it lower and lower, until it started to pass GLaDOS' chest and leave it bare, and she stopped it with a gentle gasp. Chell only smiled, and started to trace GLaDOS' collar bone with light kisses.
"Oh, please, sweetheart," Chell looked at her lover's eyes, wide with lust, and her grinning teeth latched onto GLaDOS' earlobe before giving it a gentle tug. "I know you like this. I know every inch of this body better than you do, and this is your 'happy android' face."
GLaDOS could barely gasp her response, as she arched herself in to Chell's touch, feeling across her heaving breasts. "It's just... s- so undignified..."
"Would it help if I pretended to hate it this whole time?"
"... Yes, actually."
Chell let out a short giggle, and pulled GLaDOS up for a rough kiss. More than anything else, GLaDOS savored the taste of need from her human's lips, and let their tongues dance against each other in pure lust. Pulling apart, Chell began again pulling her zipper down lower and lower. Not only did GLaDOS not stop her, but she spread her legs in anticipation, and adjusted herself to make it even easier. Chell leaned forward, and began running kisses up and down the taut muscles of the gasping android, adding in her own little dark bites to paint alongside them, until she finally made her way to GLaDOS' swollen sex.
"Ooh! Looks like somebody doesn't wear panties," Chell seemed almost stunned with what she was seeing. "Good girl! And wet already?"
Chell dipped her finger between GLaDOS' folds, and sampled her arousal as she licked it off her finger. It was a strange flavor, simultaneously powerful and sterile, and Chell immediately wanted to taste as much as possible. "Now, what are we going to do about that?"
GLaDOS shot her lover a look of disbelief. "Oh, you have got to be kidding me."
Chell gently run her fingers across GLaDOS' folds, reminding her that no, she most definitely wasn't.
With a groan of frustration, the AI whispered. "P- please, I... I need..."
The human's nimble fingers teased across her sex. "What's that, dear? I couldn't quite hear that."
"Ah! I... I- oh god, oh god, I need... gratification."
"Hmm," Chell pretended to think about it for a moment. "And how exactly would I do that?"
GLaDOS started to try and grind her hips against the human's hand in frustration. "You know exactly what I mean!"
"Yes, but I need you to say it."
"... P- please let me come."
Chell started to grin, and without a moment of hesitation, pulled herself between her lover's legs. Her mouth and fingers were moving in tandem, gently teasing, savoring just the taste of it, rubbing her clit, fingering just the right spots, and leaving gentle bites against her inner thigh, before pulling away and leaving the android gasping, and drenched in her sweat and own arousal. Finally, GLaDOS grabbed her head and pulled her in closer, before grinding against her mouth harder, which Chell absolutely didn't complain about, as her animalistic, shuddering, heaving moans shaked the room and the very core and she was so close, she had to come, she had to fucking come-
And then Chell hit the button again.
The two lovers spent several hours in the desolate chamber, away from the prying eyes of the facility, pushing GLaDOS to the very brink of pleasure and seeing exactly how far she could go.
By the time they were done, the paneling beneath them had to be replaced because of the water damage.