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Biology lessons with the Doctor

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You arrived back in your hometown Jasper, Nevada after finishing your studies and training in the medical field abroad and decided to return home to work as a doctor and a surgeon in the town’s hospital where your parents used to work at.


You were having a relatively normal life, obtaining your stable job and buying a house at the outskirts of the small town where it was peaceful and quite, surrounded by almost nothing and the night sky. Until you watched a giant alien robot crash land themselves into your dear house in a battle. R.I.P. house.


You were introduced to the Autobots shortly after the 3 kids, one of which was the son of a nurse at the hospital that you worked in… huh, small town.


Optimus thought it would be beneficial for an adult human to be at the base to watch over the children when their guardians were not around. Knowing how adventurous Miko can be and how young they were in general to fully comprehend the dangers and stakes of the war they were involved in, it was probably the most logically sound choice.


You were assigned to Ratchet as a charge, much to his reluctance. The other bots had their children charges to take care of, and Optimus already had his servos full being a prime and a leader of the faction. With your house gone, and the rest of your belongings salvaged from the rubble with the help of agent Fowler and his team, you were invited to stay at the base.


Jasper was a rather peaceful town, and you thankfully did not have to attend to many patients and had more off days than if you worked in a busy city. You spent your days watching over the kids when they arrived after school and later at the hospital for your shifts.


You tried to keep out of Ratchet’s way, knowing that he was easily annoyed but anything the kids did or if the noise got too loud. Honestly, you related a lot to the grumpy bot, having your share of stressed out moments, trying to work in a room with a bunch of (usually noisy) kids is the last thing you need.


You did your best to try to quieten the kids down whenever you saw Ratchet tense at any sudden noises as he typed and effectively decrease any of Miko’s escapades with Bulkhead. It was safe to say that Ratchet was thankful for your presence as he was able to work in peace whenever you were around and didn’t mind carrying you around the base.


You felt yourself grow closer to the red and white bot over the days you spent at the base with him. He started to greet you back when you emerged from your room in the mornings and sometimes the two of you ranted to each other, you about your work when you were stressed and him about his work and sometimes the kids.


It was after that one night that the two of you grew closer and your relationship with the grumpy medic bloomed. You were called in for an emergency in the late afternoon and was absent from the base the entire day. It was when the night crept in and the morning of the next day started that got Ratchet to worry for your safety.


You were usually back by now, but perhaps you were busy… or not? His processor started to come up with absurd scenarios that held your attention, or put your safety in danger. Suddenly, his comm rang and immediately picks it up after recognising your number. What greeted him wasn’t what he expected. You didn’t have your usual cheerful, comforting tone that made him smile on the inside whenever you talked to him.


No, your voice was low, tired, cracked. You sounded broken and it ached his spark for some reason. He opened the ground bridge to see your tiny form trudge through, you looked as bad as you sounded. He softly asked what was wrong and if your were okay, when you broke down in front of him. You lost your first patient.


As a medic and a ex-mentor, he knew how devastating losing a patient when you were working on them is like, and it was especially devastating when you first start out. The hammering thought in your processor, that it was all your fault . Ratchet saw medibots in training fall into depression after their first lost patient, some of them never returning to their normal selves.


Ratchet gently picked you up and hugged you against his chassis as you sobbed against his warm metal frame. His hushed voice whispered comforting words as his large digits rubbed your back. Going back to his habsuite, he shares his experience of losing patients, especially during war. You listened quietly, lying on his chassis where he held you. His words calmed you down significantly, your tears stopped flowing after a while and exhaustion washed over you. Soon, the two of you finally fell asleep, with you on Ratchet’s chassis as he recharged peacefully, resting a servo over you protectively.


Over the next few days the two of you grew on each other, you could almost say that he was your significant other. The both of you kept your relation under wraps, not wanting to draw attention from the kids and to avoid the other bots’ teasing. Though when Optimus found out one day and congratulated Ratchet, his face immediately turned bright blue and you tried to hold back your laughter at how cute he looked when embarrassed.


It was when Optimus was infected by the cybonic plague when you realised how little you knew about your significant other’s species, biology wise. As a doctor, you always seeked to help whoever was in need of healing, and you would help them to the best of your abilities. Which was why you took so long to study and train.


You felt helpless on the inside, despite knowing that you could not help Optimus with your human knowledge. But it was the lack of knowledge that bugged you as you saw Ratchet fret and worry over the dying leader. If you were to be a part of this team, and as Ratchet’s helping hand, you wanted to learn more about cybertronians to help him and the others.


“Hey Ratchet?” you asked one day.


“Hmm? What is it?” he looked over from what he was typing, a gesture that you warmed your heart as he turned his full attention to you.


“Would you mind if you taught me about cybertronian biology, and I well, can teach you about human biology? We could both benefit from it, in case something happens to me or the kids that normal human methods can’t fix and I can help you with patching up the others.”


“That sounds... reasonable. I could use a helping hand around here.” He says smiling before going back to his work.


And thus began your nightly lessons with the much less grumpy medic. Both of you set aside some time before recharging to go over a portion of both your biological knowledge. You shared with him the notes that you took down when you were in school as a condensed form of reference and he hands you his share of translated data pads. Being experts in your own field, teaching each other was a breeze as you learned about how similar and different human and cybertronians were.


There were also some, more hands on sessions where the two of you would observe each other’s bodies with your hands and his large servos. Gently moving each other’s limbs to watch how your anatomies worked. Sometimes ratchet would displace some of his mass to shrink down and match your tiny human form so that you would have access to his otherwise much large pedes and arms.


He was still larger than you in his shrunken down form. His large servos gently pinching and prodding your skin as he stared in wonder at the softness of your fleshy nature always brought a warm blush to your cheeks. You felt as if you grew intimately closer to the usually distant medic after every session, but you decided not to keep your hopes up.


The two of you were supposed to be professionals, and these little sessions were merely for educational purposes, nothing more than that. Plus, Ratchet would probably be the last one in the Autobots to ever think of having a relationship, much less an intimate one with a human.


That night, Ratchet and you were planning to go through… your reproductive systems. You tried to think of ways to convey information to im in the least awkward way possible. The reproductive system and ones… intimate parts was a topic you never understood why your teachers disliked talking about, until now.


Paired with your boxed up hidden feelings for the medic, your job could never be harder as a blush started to creep to your cheeks when ever you thought about the lesson later that night. You shook your thoughts away and focused on your job as a patient entered the room.


Get yourself together. You’re a doctor for crying out loud. You’ve seen other patient’s intimate parts without batting an eyelash, why the heck are you blushing about teaching it to Ratchet?


You rushed back to base after your late shift that went slightly over time later that night, not wanting to keep Ratchet waiting for your lesson with him. You called him with your phone at the back alley of the hospital and a shimmering ground bridge opens up. Looking down you realised you hadn’t changed out of your white coat, having rushed out of the place. You hoped Ratchet wouldn’t mind.


The minute you stepped through the ground bridge, Ratchet’s cooling fans kicked on to its lowest possible setting. Seeing you in your professional attired awakened something in the old medic, it was almost embarrassing as Ratchet fought to control the energon that was creeping up to his faceplates. Thank Primus the others were out on their different duties and patrols.


He listened silently as you talked about how the human body reacts before sexual intercourse, its temperature rises, the heart rate and intake of oxygen increase, the genitals begin to swell and produce lubricant and the brain produces a bunch of chemicals and hormones to stimulate the reactions.


That sounds… very similar to what he was currently experiencing if he were to put it into a cybertronian context. His optics were locked on to you as he watched you keep a straight face, back facing him as you wrote down points on the board, giving him a full view of your soft juicy ass. His fans unconsciously kicked up a few notches to the point where you were aware of them.


To be honest, you were trying desperately to keep a straight face and not look at Ratchet as the same reactions that you were scientifically listing out were happening to you too. Though, being a female of your dear species the reactions were not as obvious and you were relatively good at hiding it, you think.


Ratchet continued to watch you form as you turned to him, optics focused on your soft lips as you talked. His mind wandered as he thought of your lips on his. Your soft, fleshy lips on his harder face plate with his glossa dancing with your tongue. He noticed that you were taking more breaths than usual and your face was slightly flushed. Were you feeling the same as he was? It matched most of the descriptions.


No no no, this was supposed to be a professional lesson, you were staying up with him to teach him and learn, it would be rude to think that of you. There must be an explanation- Tell yourself what you want Ratchet, but there is no professional answer for this! He felt his processor yell back at him.


“Ratchet.” your sweet voice called out to him, waking him up from his distracted mind.


“W- what, sorry could you repeat that?” he quickly covers.


“Are you okay? Your fans are getting pretty loud, isn't overheat for prolonged periods bad for cybertronians?” your hand brushed against a transformation seam on his arm and he gasped slightly at how sensitive he was at the moment. His spike pressuring against his interface panel at the sudden contact with a mix of the heated emotions he was experiencing.


“Why don’t… why don’t we have a more hands on lesson today, hmm?” his lidded optics gazed down at you as his cooling fans increased in speed once again.


You looked at him with wide eyes, did- did he know ? His passionate gaze sent a shiver down your spine as blood rushed to your face and down south which you knew was already drenched. You let out a heated breath “S-sure, Ratch.”


Immediately shrinks down you your level and pulls you flush against his warm, heated frame as he cups your face. “Increased temperature, breath intake quickening, heart beat increased and blood rushing to different parts of the body. Would I be wrong to say that you feel the same way I do, my dear?” he hums.


You let out a chuckle as your fingers ghost along the wires on his neck, making him flinch at the contact and his cooling fans were probably on its highest setting. “Why don’t we continue this lesson, our way ?”


You pulled him down to meet his lips with yours, his glossa immediately licking your lower lip asking for permission. You giggled at his excitement and let his glossa intertwine with your tongue in a hot passionate kiss.


Your arms pull away from his frame as you started to unbutton your top, wiggling both your coat and top off as you started to remove your bottoms. “Wait.” Ratchet says breaking away from the kiss. “Can you… keep the coat on, as we um… interface?” he says blushing, looking at the discarded white coat on the floor.


Huh, of all things you never thought of him liking the coat. You smiled coly at him “Doctor’s orders~” you turned around to unclasp your bra and took it off before putting the coat unto your bare upper body, the material just covering your erect nipples as you turned around to face the heated medic.


His cooling fans were practically roaring at the sight of you in just your coat and panties. His wandering servos cupped your incredibly soft breasts as his mouth latched onto a nipple, glossa immediately worshiping the hardened bump on your supple chest. He had read your notes prior to the session as he waited for you, and it equipped him with enough knowledge to know where to elicit a response from you.


A hand went up to your mouth as you tried to hold back a moan. Your response only spurred Ratchet on as his servo traveled to your nether regions, making sure to ghost his digits on the way. Your muscles tensed and rippled at the action, letting a muffled moan behind the back of your hand. His mouth went back to kissing you as his digits stroked your swollen mound.


Your fingers danced along his neck wires as the other hand rubbed the exposed transformation seams on his lower back. You moaned against his mouth as his digit rubbed against your clit through the soaked material, pushing your hips forward against his servo for more friction and contact.

He pushes you against his berth and lays you down on the material. Breaking from the kiss, Ratchet rises from your form on the berth and takes in the scene in front of him. You, panting, heated, sprawled on his bed with your pearl white coat framing your sides like folded angel wings as he kneels in between your legs. It was too perfect.


He tucks a digit under the elastic of your underwear and glides it off your legs, the amount of natural lubricant on the fabric created a translucent thread that connected the soiled material to your wet entrance. Your eyes widened in embarrassment at how wet you were before covering your face with your sleeve in a weak attempt to hide from him.


Ratchet lets out a low chuckle before dragging his glossa along your dripping mound and stopped at your clit to begin sucking on the swollen node. In return, Ratched received the sweet gasps and delicious moans from your lovely lips, music to his finials. Inserting a digit into your entrance, he noticed how much softer, wetter and warmer it was compared to a valve.


“You’re so wet for me.” he says licking your clit as he easily inserted another digit, spreading you further. His low voice vibrated through your core as you tried to push against him eagerly.


“Ratchet, please.” you whined.


Ratchet hummed before rising again, finger leaving with his mouth leaving you empty and needing for him to fill you. You watched as his interface panel disengages to reveal his fully pressurised spike. It had the same red and white colour scheme patterned on it with blue bio lights lining the sides. And the size of him- he was definitely bigger than the average male and was more on the thicker side. You panted as you reached down to stroke his spike.


Ratchet more than welcomed your hand as he positioned himself over you taking your lips in another passionate kiss as you guided him to your soaking entrance. Receiving the invite and consent, he started slowly pushing into you allowing you to adjust to his size.


You moaned into his kiss as he gently thrust in and out of you, burying deeper into your core with each entrance until he was fully hilted into you. Your muscle walls squeezed around him as you begged him to continue. “Ratchet, please more, I need you.” you hugged his back, pressing against the transformation seams that you knew of.


He chuckled at your plea “Doctor’s orders.” he returns your reply and starts thrusting into you.


You held on to the curves of his back armor as he rocked you into the berth, whispering sweet nothings to you in cybertronian as you gasped and moaned his designation over and over. His thrusts became more rapid as he held your hips against his, reaching his overload. You too were reaching your climax as you told Ratchet to keep going.


His cooling fans continued to roar as he overloaded into you, transfluid filling you up as your muscle walls spasmed and rippled around his spike as you reached your peak. Ratchet held you against him as he turned over on his berth with you lying on top of him, panting. The two of you stayed like this until you’ve caught your breath from all the excitement.


“You know, we never actually learned anything just now… wanna go again?”