This inspired a short story which I would like to share. Ahem. I apologize. I think I may have gotten a bit too carried away. Warning! Mature content. Reader discretion advised. Part 1
Dash: H-hey! T-Twilight what are you doing?!?
Twilight: Shh. Relax and hold still. I just want to try something...
Twilight wrapped one of her forelegs around the cyan mare's neck. She gently pulled Rainbow closer, and covered the mare's eyes with her other hoof. Dash struggled a little, not sure if she liked what was happening. She suddenly went stiff when she felt the unicorn's hot, wet mouth engulf one of her ears...
Dash: T-Twilight! L-Let go....ngh...<3
Twilight (snickering): You're enjoying this, aren't you Dashie?
Twilight gnashed her teeth gently, noticing the way Rainbow's left leg twitched in ecstasy the harder she bit down. This gave Twilight an idea. Twilight took her hoof off Rainbow's eyes. She saw with satisfaction that the Pegasus was biting her bottom lip, and that she had flushed red. Her eyes were shut tight in pleasure. Twilight ran her hoof up Rainbow's flank, tracing the lightning-shaped rainbow and cloud that was the mare's Cutie Mark. Slowly, Twilight moved her hoof to her friend's crotch, where she began to gently rub at the moist slit. Rainbow's eyes shot open when she realized what Twilight was doing. She leaned her head back, rose eyes wide. Her tongue lolled from her mouth as she began to pant. Perspiration broke out on her forehead. Dash's left back hoof repeatedly collided with the floor, growing faster with each tap. Her wings spread out wide on either side of her. Twilight smiled, and rubbed harder, causing her winged companion to moan out loud.
Dash: Ahh... hah...so. Awesome! Ngh!
Twilight: Hahaha... getting a little wet down here aren't you Dash? Such a naughty pony...
Dash: L-Look who's talking... Ngh...
Twilight: Hmm... maybe we ought to step this up a little. How to go about it though is the question...Now let's see...
As Twilight thought, she sank her hoof in a bit deeper. Now she began a brisk swirling motion that sent Rainbow's wings flapping and her leg jerking on the floor. Any second now she would reach her climax. Suddenly, an idea struck Twilight.
Twilight: I'VE GOT IT!!!
Twilight had just finished this sentence when Rainbow let out a scream. She collapsed onto her side, leg still spazing hysterically as juices splashed from her crotch, coating her flanks and forming a puddle on the ground. Twilight smiled, and withdrew her hoof from Rainbow's crotch, licking the sweet cream off it. Rainbow Dash watched her, a dazed smile on her face. Her face was flushed bright red.
Twilight: Mmm... Skittles.
Dash let out a weak chuckle. She looked ready to pass out, but Twilight had other ideas.
Twilight: Not so fast, Dashie. We're not through yet.
Dash (horrified): W-we're not...?
Twilight: Dear Celestia, no! THAT was just a warm up! I hope you're body is ready Dash. <3
Dash: R-ready? Ready for what?
Rainbow Dash was helpless. Using her magic, she dragged Rainbow Dash up the stairs to her room to give her friend a hot bath. This would be the best night ever.