Twilight’s eyes bugged out as she looked into her kitchen, and more importantly, the pony within, her rump swinging from side-to-side as she searched through the fridge. “Rainbow… what are you doing?”

Rainbow Dash’s head turned over her shoulder. “Oh, hey Twi,” she greeted, smiling before she stuck her head back in. “Say, where’s all the milk and stuff? All I can find in here are these bottles, and none of ‘em look anything like milk.”

Twilight sputtered, trying to formulate her words as Rainbow stuck her head in further. “Ah, here we go.” Rainbow’s muffled voice came from somewhere within the fridge, a bottle clasped in her mouth.

Her eyes widening, Twilight darted forwards, shouting: “No, no, no!” even as Rainbow spat out the cap and tipped the bottle skywards. When she reached Rainbow, she hit the bottle, propelling it sideways so that it smashed against the wall.

When she turned back, she met Rainbow’s glare with her own. “Do you have any idea what you just drank!?” she exclaimed before Rainbow had a chance to open her mouth.

Rainbow shrugged, still glaring at Twilight. “Milk, right? That’s why it was in the fridge in the first place.”

Twilight sighed, “This isn’t the food fridge, Rainbow, this is the fridge where I store all my potions for crying out loud.” She swung the door shut, the piece of paper tacked onto the front now clearly visible. “See? ‘Twilight’s experiments. DO NOT TOUCH.’”

Rainbow rubbed her hoof against her head bashfully. “I was hungry…” she protested weakly before she froze. “Hang on…” she began, worry starting to creep over her features. “If… that’s your potion store… then what did I just drink?”

Twilight sighed, slumping down and using her magic to gather the remnants of the bottle together. “That’s just it… that was one of the potions that I’ve not had a chance to test yet. It could do anything.”

Rainbow gulped, sitting back herself. “So… you don’t know?” she confirmed, dreading the answer. Her stomach rumbled and her hooves shot down, hugging her tummy to herself. She watched Twilight shake her head silently, her expression grim. “Oh my god…” she muttered to herself. She could feel the panic setting in but couldn’t do anything to stop it.

“I just drank that and you don’t know what it does, and if you don’t know what it does then no-one knows what it does. It’s going to kill me isn’t it? I just drank something poisonous; I’m going to die aren’t I? I don’t want to die! I want to live!”

Twilight wrapped Rainbow in a hug, trying to calm her marefriend down with a calming voice, “You’re not going to die… I promise, come on. Let’s go down to the lab.” She stood up, pulling Rainbow with her. “Let’s get you tested out, I’m sure it’s nothing fatal at the very least.”

Rainbow snivelled quietly, allowing Twilight to lead her down to the basement and the laboratory within. The room lit up as they walked through it, showing the various gadgets and machines within. Twilight led her into the centre of the room where a few cushions had been sparsely arranged. Rainbow collapsed down onto one of them, her hooves shaking slightly.

“Stay right there…” Twilight said, backing away and shooting panicked glances around the room. “I’ll be right back… I just need to remember where I put the potion stuff.”

Rainbow nodded, watching Twilight speed off. She felt her stomach do another turn. “Hurry!” she called after her, pressing her hooves into her stomach.

She kept them there until she felt her tummy settle. Was it her imagination, or was it hot down here now? Her breathing quickened again and she started to hyperventilate, calling out into the basement, “Twi?” The walls were closing in on her, there was no escape, she was going to die down here. “Twi…” Her voice came out in a whisper, barely audible to her own ears.

She felt her stomach stir again and a heat started to spread out from between her legs. Suddenly, gasping in surprise, her hooves abandoned her chest and focussed between her legs. She gasped again as she touched her sex. It felt swollen and puffy, heat still radiating from it in great waves. The heat paused for a moment as her hoof passed over, then it started spreading again, causing her to squirm uncomfortably.

She needed it to stop, this was too warm. Her hoof sought out her slit once again, pressing it and stroking it, trying to stop the heat from spreading again. She moaned. The heat kept spreading. She needed a release or else she was going to burn up! She pressed her hoof into her slit again, pushing it deeper than before and using it to rub herself off.

She closed her eyes, rolling back onto the cushion and trying to go faster. She could feel the heat slowing down as she kept going, faster and faster. She moaned again, trying to force her hoof further and further, faster and faster. It felt so good. She didn’t even notice when the heat started to fade away, this still felt like heaven as she rubbed. This was no-longer about trying to stop the heat, this was about trying to prolong the wonderful sensation that her groin was emitting.

Her breath hitched as she hit her orgasm, eyes rolling beneath their lids as the liquid spilt out across her hoof and coated the cushion beneath her. She laid there, her hoof still inside her as she caught her breath. Her ears flickered; she thought she could hear the sound of approaching hooves.

“Rainbow! Are you alright, I heard you calling an- Rainbow… what happened?”

She could picture the look on Twilight’s face. Accusing, disappointed, annoyed. Rainbow cracked open her eyes to see Twilight gazing down at her, her expression flushed. “I- It’s not what it looks like!” she protested vainly, withdrawing her hoof from her soaked snatch with an audible ‘pop’.

Twilight stayed silent.

“So, uh…” Rainbow started, “I think I found out what that potion did…” She could feel the heat starting again, focussing on her still-slick rear and expanding outwards.

“You did?”

Twilight’s voice was weak and faint from disbelief. Rainbow nodded silently in reply as she shifted uncomfortably, trying to ignore the spreading warmth across her nethers. “Yeah…” she started, licking her lips anxiously. “Good news though… I don’t think it’s going to do me any real harm.” Her eyes roved over Twilight, drinking in the sight of her.

“Well…” Twilight started, her blush still suffusing her face, “That’s good.”

Rainbow nodded slightly, still shifting about slightly against the increasingly uncomfortable heat. “Twi?” she queried distractedly as her gaze shifted further down Twilight.

“Yes Rainbow?” Twilight replied, shifting backwards nervously as Rainbow kept her gaze locked.

“Have I ever told you that you look hot?” Rainbow said in a dreamy voice as she shifted about on the floor again, moving onto her hooves. In front of her, Twilight sputtered in surprise.

“Well- yes- well- sometimes- well- when you’re… when you’re…” Twilight gulped but didn’t step back, looking at her marefriend with a mixture of fear and wonder.

Rainbow Dash smiled a predator’s grin and pounced forwards, the heat driving her onwards.

Author's Note

Actually written a while ago...

Woo for short sex scenes with open ends :P

This is my cue to run...