An Optimus X Hybrid Reader as suggested by @BethanyGregerson 

Warning: Mildly disturbing content (broken bones)

Hope you enjoy!

(Y/N) - Your Name

(F/C) - Favorite Color

(H/L) - Hair Length

(H/C) - Hair Color

/~\

         "I'm not as willing to judge a human as I am a Decepticon," Ratchet admitted, "But this one I have my doubts about."

They all stared at the hunched over figure of (Y/N), who drew in the pile of dust she had swept up. Mind you this wasn't a small pile from the day's goings-on, this was from three or four years of the bots going in and out of the missile silo. The team cringed as they realized how... unclean the main area was. She had swept it out of the way in a corner, so they were at least thankful of that, but what puzzled them was the fact she didn't sweep to clean up, she swept to draw in it-

         "Ratchet, she was extracted from MECH's clutches, she is fortunate to be alive. I believe we can assume she is not exactly like the rest." Optimus advised, taking the few steps to join the young woman who looked up with (F/C) eyes curiously. Her (H/L), (H/C) hair waved in the slight breeze his joints made as the titan kneeled beside her. "(Y/N), can you understand us?"

     She blinked at him, hissing as her neck twitched from looking up to long, but nodded. The girl coughed as the dust in her nose filtered into her throat, her drawing fluttering away. She frowned at this, trying to bring back the finger drawing.

         "I don't think this is sanitary," Optimus told her, but the human female ignored him, resulting in him picking her up so she didn't make her condition worse by playing in the dirt. 

He placed her on the high medical berth, turning to talk to Ratchet when they all heard a 'splat'. 

         "She jumped!" Jack pointed while Miko hid Rafael's eyes from the broken legs that now bent in different directions not humanly possible, almost throwing up.

         "I told you she was unstable!" Ratchet hollered at Optimus, who held an expression of guilt and mild horror as the body refused to move- until a loud 'snap' came from the mangled human.

     Several more occurred and Miko finally threw up, leaving Raf on his own to watch the show as (Y/N)'s legs snapped back together with a sickening sound, the rest of her body still limp. When the freak-show finally ended, it was another minute of horrified silence before she stood up as if nothing was wrong, walking back to her dirt pile. She sneezed and the others flinched.

         "I think I'm going to be sick-" Rafael muttered.

         "I think I'm going to get that scan to hurry itself along-" Ratchet started typing again, admittedly spooked.

What did MECH do to her?

     The next day (Y/N) was found popping her knuckles, but upon further notice she was actually separating the joints- Jack, Miko and Raf didn't want to be near her, despite not wanting to judge a book by it's cover. Unfortunately, this horror story seemed a little to terrifying. Optimus was surprised they took the invitation to go home for the day, watching them all 'escape' from the new roommate. He looked to the young woman who had moved on to her toes, her fingers having knit themselves back together once she had finished pulling them out of socket.

         "Do you not think this unwise if it scares your fellow humans?" Optimus questioned, earning a blank, (F/C) stare in return. He gave a sigh, picking her up. "We understand you were experimented on while with MECH, if we can reverse it, we will, so you may live a normal life; if not, then you are welcome to stay with us."

     The girl tilted her head, curling into his warm servo instead of giving an answer. He believed she was about to fall into recharge- or sleep, as the children called it, but was gravely wrong as she flexed her back, spine popping from her tail bone to her skull. She looked back to Optimus.

         "Hard to not do it when it both fascinates you and relieves pressure from the metal wiring that holds you together."

The Prime couldn't help but show his surprise, the human female in his palm sitting up with a tired expression.

         "I would have spoke earlier but human ears can't hear my voice unless given a hearing aid. You hear me most likely by turning up the volume or whatever."

Indeed, Optimus had to adjust his audio to hear this tortured human, memorizing her vocal pattern then quickly turning it down before someone called him.

         "Well, now that you feel comfortable enough to speak, may I ask you a few questions?"

     (Y/N) nodded, gladly answering all she could about her kidnappers. From the dog tags on her chest to the strange ability to patch herself together from almost any injury. She was in the Military, fighting overseas when her platoon was ambushed by an unknown enemy. All died in some experiment, but she was cursed to live through the transplant of wires, which was the first step of many. Next came the nanite injections that still burned with every movement she made, the alterations to her vocal cords, the strange change in her eye color (of which she still didn't understand) then the unseen acuteness of hearing. This change was necessary in order for (Y/N) to hear herself.

     Optimus took charge of this human, knowing Ratchet was far to busy and the others couldn't care for a human with these cursed yet special abilities. It would place stress on the children, and therefore stress the bots out as well. Several weeks slipped past, (Y/N) being a large help to the Prime as he got himself in narrow situations. He started to realize why Soundwave held Laserbeak so dear, but (Y/N) wasn't a minicon. She was still far more fragile, despite this seeming invincibility and far more reckless. She had explained why one night, staring at the stars with Optimus Prime, this recklessness. She knew if she were to die, she didn't want it to be from just sitting in a hospital bed, useless. So here they stand once more, staring at the stars in a comfortable silence.

         "I did not appreciate you disobeying my orders today."

         "I didn't appreciate you going into that ticking time bomb of an energon mine," she spit on the ground, glob of blood and saliva steaming off the rock, not from the by now cooled rock of the Nevada desert but from her natural body temperature being far to high to not melt her- if it weren't for the alterations, anyway. "I defused that grenade, didn't I? If Wheeljack wasn't so stupid I wouldn't have had to anyway."

         "Perhaps, but being so close to that grenade would have blown you to the far galaxies. Not even your alterations could have saved you from that. Wheeljack and I would have survived."

It was quiet, but (Y/N) soon started laughing, earning a confused expression from Optimus.

         "Did you see his face when I jumped on it?" she wiped a tear from her eye, the moon illuminating them as if to make them glow in the perfect night. Optimus let a small smile grow on his derma, nodding, "'You can't defuse a grenade'- Glitch, watch me!" Her small laugh, barely a whisper, tickled the Prime's audio. He enjoyed hearing it. She was sarcastic but not a nuisance, and despite the torture she was forced to endure, she still loved to laugh. More so once she had been out of the range of MECH for several days.

     Optimus continued to admire her as her mirth dialed down, and he picked her up upon her request, bringing (Y/N) close to his faceplate. They stared at each other for time before (Y/N) kissed his upper derma, surprising the mech.

         "Thank you."

         "For what, may I ask, is this show of thanks for?" He tilted his massive helm.

         "Everything," she chuckled, "from giving me the benefit of the doubt to trusting me even with your life. I haven't felt needed since I was in the Military. To be honest I thought I'd die on that operation table." She was quiet for awhile, staring into those soft blue optics of his. Her expression was one of gratitude.

         "(Y/N)," Optimus began, "How would you like to become a permanent asset to our team?" 

He watched as her eyes lit up with excitement, her smile even wider. This meant she wouldn't have to go to a Military hospital like Fowler said she would-

         "Absolutely!"

With another quick kiss to his upper derma, she attempted to jump off to tell the others the good news, despite their awkward stances around her. Optimus caught her though, making the woman pout.

         "I'd rather you not break your pedes... again."

/~\

And there you go! I hope it was what you were hoping for. If not, awfully sorry. 

Thanks for reading!