All credit for the concept of this story goes to Shinodage, artist for the original Magic Touch comic. I've had a shameful obsession with this comic for a long time, and decided to put my fragmented self-insert fantasies into writing. Not sure if I'm going to do this for part two, I don't think this is good for my mental health haha.

The green unicorn hummed a happy tune as she walked down the Ponyville street at dusk, having spent the day busking with her lyre in the park. As she approached her apartment, the ground floor of a small house on the edge of town, Lyra took out her keys with a jointed appendage with five digits she rendered with her magic. She learned about these "hands" in her reading into cryptozoology, hairless primates with a penchant for technology used them to build their machinery. 
As she went to unlock her front door, she was startled by a "Hey!" from directly behind her. She turned her head to look at the stallion, "you're that mare with the magic hand!" he exclaimed. Lyra didn't recognize the pegasus stallion, he was about average height with a dark coat and a very light blue mohawk and short tail, his eyes were the same gold as hers. His cutie mark was a thundercloud with lightning, and Lyra noticed he had toned muscles despite his average stature.
Unsure what to make of his enthusiasm, Lyra slowly said "...yes?" "I saw you a the park earlier, giving some lucky stallion a hand!" the stallion chirped. Lyra, more startled now than when he snuck up behind her, snapped "you what?!" Before heading home earlier, her earthpony friend Caramel was listening to her playing after everypony else had gone home. Lyra knew he had a busy week and didn't have a marefriend, they got to talking and she figured she could help him blow off some steam. She had a few stallion friends around Ponyville who didn't have marefriends of their own, they all worked hard and she didn't know how they would get relief without magic. She didn't mind helping them with their needs, there were no expectations and she didn't even have to touch them besides with her magic. It wasn't a secret that most stallions found Lyra cute, so usually they didn't take very long to finish, either.
"It's a public park, you can't expect to go unnoticed," the dark stallion replied. Lyra swore she checked for any onlookers, he must have hidden in a dark treeline to observe their fun. "Point is, I'd love to experience that too. What do you say?" he asked. Lyra's face was flushed and she turned her ears down, this was a bold request from the stranger and she needed to make herself some dinner. Looking away, she started "well..." before being interrupted by the stranger "I have bits~" The rest of her breath was spent in a huff, she could've guessed where this was going.
Truthfully, Lyra wasn't sure if her meager earnings from playing her lyre were going to pay her rent this month. Sure, she could move back in with her parents in Canterlot, but she was enjoying her time in Ponyville since moving there after her schooling. This wasn't much different than doing a friend a favor, right? "Alright, come in," she droned as she unlocked her front door, the dark pegasus' impressive wings perked up at this.
"Get comfortable, I guess," Lyra said as she set her things by the door, "just don't make a mess-" A thudding chime interrupted the unicorn as he placed a sack of bits on her table. The sack easily contained more than she'd made busking in the last two weeks. Fixating on the sum, she muttered "that's a lot of bits..." The stallion interjected, "I expect an ace job," already lounging on Lyra's couch with his legs spread. She swished her tail and smiled as she turned to the stranger, "Well, let's not waste any time, then." She didn't think of herself as the sort of pony who would do this, but she did need the money and he was the sort of stallion most mares would fight over.
Lowering her gaze as she walked over, she got her first look at his gear. His tip was already starting to emerge from his wide sheath, his package a darker charcoal than his coat. "Look at that thing..." she said in a sultry tone as she sat her flanks down on the floor with a *pwaf*. She motioned her magic hand under his package, which drooped off the edge of the couch. She lifted his balls and his slowly emerging shaft with it, "It's so heavy-" A shaky groan interrupted her as the pegasus nodded his head down, his shaft suddenly doubling in length with a violent spasm. Lyra's hand gently moved up his hardening, dark appendage and her thumb met a bead of precum that had already formed at the tip. "And, wet... that was quick" she spoke softly as she felt her face begin to flush. She had never interacted with a stallion who could get aroused this quickly, and his cock was already impressively girthy as it continued to grow.
"You ok, there?" she asked as she grasped him above his medial ring, it looked like he was almost ready to faint from the blood that was redirected to his stallionhood. "Yeah," he stammered out, "keep going." Lyra slid her hand down his lengthening shaft, leaving a slick trail of his pre from his tip leading down. His thick penis throbbed again as her hand passed his medial ring, more of his clear gel spilling out and slowly running down the bottom of his tip. He wasn't much longer than other stallions Lyra had played with before, but he was far thicker she noticed, as her fingertips were a couple of inches from her thumb holding him near his larger-than-average balls.
"Feels good?" she cooed, drawing her hand back up to his head and spreading his shining juice over his head. "It feels amazing," he droned out, his shaft now fully hardened in Lyra's grasp. She slowly increased the pace of her stroking as he continued to leak. Lyra wondered how long he went without cumming, if he was a quickshot, this would be much less hassle for her money than playing her lyre in the park for hours.
"Now," the dark stallion said, leering down at the slender unicorn sitting between his toned hind legs, "let's see if your mouth can handle it." Lyra felt her heart begin to pound and a profuse blush form on her face, "what?!" She thought he only wanted her hand, she gave a few of her stallion friends around ponyville a lick every now and then while giving them a handy, but she could infer he wanted more than that. The kind of deep, intimate oral she only gave once to a unicorn colt she had a brief romantic fling with in Canterlot. "But you only asked for a hand-" "ACE job, remember?" he interrupted. 
The worried mare paused, her blush growing as she realized this stranger was twice as thick as the teenaged unicorn she was involved with, how would that thing fit in her mouth? He was certainly strong enough to take what he wanted from her if she wouldn't give it willingly, and she didn't know his character or motivations. "Well?" he interrupted her thoughts, punctuating his question with a twitch of his cock, his wide cock head swelling briefly and its skin flashing in the dim light as it was pulled tight. Oral felt like something special that she should save for someone who cared about her, but she couldn't deny how hot this guy was. Lyra slowly opened her mouth as she brought her head closer to his cannon, which invited her by gushing more of his nectar. The mare was nervous, but more aroused by his pressured advances than she'd ever been before.
"Good girl," the stranger encouraged, as the unicorn mare drew her trembling lips closer to the end of his penis. Lyra would normally be taken aback being talked down to like this, she knew how roving pegasi legions would take unwilling unicorn mares as their fucktoys in pre-Celestian times, and how many of them still think of those times as their "glory days". Her focus was instead on keeping her mouth wide enough to accomodate the shadowy pegasus' girth. The shame in the back of her mind melted away in the heat of his cock musk, his athletic sweat and precum scent triggering a lust in her damp marehood greater than any she'd ever felt before today.
Lyra's tongue met the virile pegasus stallion's swollen tip, his precum was salty and had a mild, pleasant musk. Her upper lips touched the front of his head, she gaped her mouth even wider and stuck her tongue out as far as she could so that the upper ridge of his flare could slip past her lips. She let out a long moan through her nose as he gushed more of his delicious salty nectar on her tongue. Her magic hand pulled his cock's skin tight as she lowered her head down his length. She formed another hand and slid it down her chest and inner forelegs, her lust demanding more stimulation as she submitted herself to this brute. 
As Lyra's lips approached the dark stallion's medial ring, her other hand started playing with her small teats. She was already wet, and pulling on her sensitive flesh made her clitoris wink and drip its own nectar. The head of his cock was at her throat's entrance and her jaw was pulled as wide open as she could, but she knew he wanted her to take him deeper. She sucked on his length as she withdrew a short distance and took a jagged breath, then relaxed her throat and slid his meat deeper. He started to exclaim "fffuuuck!" as her lips slid over his ring, and his tip swelled as it pushed into her throat. His thick shaft twitched again, stronger this time as his veins pulsed against her soft tongue. Lyra felt her clit wink again as she gushed more liquid from her aching hole.
"You're really good at this," the dark pegasus moaned as the tip of Lyra's tongue lapped at his balls. His cock was completely buried in her mouth, and she realized her eyes were shut, immersing herself completely in he lewd service to this stranger. She opened one eye to look up at him as she slowly withdrew her head from his twitching cock, his flare leaving a salty trail in her mouth as it popped past her throat and then her lips.
"I am?" Lyra asked, multiple strings of her saliva and his precum still connecting her mouth with his completely swollen cock, the sturdy base of which she squeezed with her hand. He chuckled, just muttering "yeah," as Lyra moved her other hand lower to her dripping pussy. "Well," she said as she lifted her long tail and parted her entrance with her fingers, "you paid for an ace job." She submissively lowered her ears as she inserted her middle and ring fingers into her marehood, licking a stream of pre from his twitching cock and then cramming the oversized thing back into her mouth. She bobbed her head down his length a few times and rapidly masturbated herself nearly to orgasm by hooking her clit with her two middle fingers. Lyra's heart was racing and she needed to come up for air soon, but she was getting close and his girth spreading her mouth made her imagination run wild on how he could ravage her virgin marehood.
Suddenly, Lyra felt the stallion twitch and tasted another large burst of his salty nectar as he grunted "mmfff, I'm..." and shoved her head down his length with his forehooves, thrusting his cock into her mouth as his body shook. The forelock of her mane was pinned over her eyes against his muscular body as Lyra's lips were pressed into the brute's sheath, she felt his cock head flare and nearly double in size in her throat. Her concentration and magic were sapped by his sudden violation of her face as she hung near orgasm, the big vein on the underside of his girthy cock pressing even harder against her tongue in violent spasms. Lyra quickly lost count as jet after jet of virile pegasus semen hit the back of her throat, rapidly filling any available space and leaking past her lips. She attempted to swallow his overflowing, musky cum, but his flared head in her throat made that impossible. She struggled past his intoxicated grasp on her head and popped his flare out of her throat, making him grunt and shoot an even larger spurt of his thick, bitter cum onto her tongue before she could get his flare out past her lips.
Lyra swallowed hard, the massive volume of cum filling her stomach in place of the dinner she had planned to make. The black pegasus shaft continued to bounce wildly in front of her face, covering not only her face, but also her couch and floor as she gasped for air. Lyra felt an odd menthol feeling in her mouth and throat as his semen left a clingy film on every part of her mouth. Breathing his overpowering musk as his cock twitched, flopped, and dripped the last few spurts of his cum out of its flared tip, Lyra complained, "I dunno what your idea of an 'ace job' is, but I could've used a warning." The jerk had his head tipped back in ecstacy as he groaned, "uughh, fucking awesome," riding out his powerful orgasm. She continued, "and look at this mess, someone has to clean this up now."
The black pegasus suddenly became alert, saying in a sarcastive cadence, "oh no, look at the time! Well, gota get going." He hopped off the soiled couch and walked toward the door, leaving a trail of cum and saliva on the floor behind him. Lyra shouted "hey!" as she followed him with her gaze, accidentally dripping more of his cum on the floor as it flowed down her face in many thick ropes. The pegasus had the nerve to shoot her his "wing guns" as he slyly said, "sorry honey, but hey, that was great! If you want to earn more bits, come to the gym tomorrow. We can talk more over there." As if he needed to further cement the fact he saw her as a toy, he added, "and pick up something cute to wear." 
Lyra sighed as he slammed her front door as he left, her gaze shifting toward the bits he left on her table. She glanced at the strings of cum still dripping down from her mane, and remembered the tightness in her pussy. Her aggrivation grew as she realized she was soaking the floor herself. She tried to ignore his douchebaggy demeanor, instead thinking about his fat cock and how she choked on his virile load. She conjured another hand and started rubbing her needy pussy again. Looking back at the couch, she noticed the drips of his cum, then the sweat stain where he was seated. Acting on lust alone and barely believing her own actions, she laid down on the couch with her face where that pegasus thug sat. She inserted three of her magic fingers into her pussy as she huffed his musk out of the couch, his scent making her shake and get close to finally having her own orgasm.
Her shame vanished behind her growing lust, Lyra licked the stallion's cum off of her couch, her pussy winking and squirting as she enjoyed the musky, bitter flavor. Her magic hand on her pussy was just not creating enough friction, she wanted to cum now. She still felt the slickness of the cum on her throat and mouth, and noticed how it enhanced the friction of her tongue when she moved it slowly. A small part of her conscience pleading her to stop was silenced by her overpowering lust as she picked up one of his cum ropes from her face with her fingers, bringing it toward her pussy. She wasn't in heat, so this should be safe, right?
Lyra's legs shook as she spread the athletic pegasus' cum over her clitoris with her magic hand, she immediately grabbed more of it from her face and started grinding it into her marehood. She imagined how violently his thick girth would stretch her pussy since she was still a virgin. Her trepidation and shame at the thought of giving her virginity to the dark pegasus thug only fueled her raging lust and made her heart hitch in her chest.
Lyra's entire body spasmed as she reached orgasm, moaning loudly as the feeling of that tool's cum made her pussy violently clench against her fingers. Her clit winked rapidly as she squirted her own nectar and some of the stallion's cum all over the formerly clean part of her couch. Her tongue stuck out of her mouth to catch another string of cum dripping from her horn as she rode out her ecstacy. 
That night, Lyra fell asleep on the couch and dreamed about all kinds of lewd, forced scenarios with big, masculine stallions she never would have imagined before. She awoke with an insatiable horniness. "I better pick up something cute to wear," she muttered as she left a trail of her nectar on the floor leading toward her front door.