Optimus had always loved Ratchet's optics. If you asked him, he would deny the way he often found himself staring wistfully off in the doctor's direction. It was all professional concern for a mech who simply didn't know when he needed to rest and recover. If he shared a glance with Ratchet for a little longer than normal, it was simply because he cared. That was what he told others. Whether or not they believed him was up for debate.
But beneath that veil of half truths created for both his and Ratchet's safety, Optimus's affections ran deep.
Even before the war, he'd loved those optics. Ratchet's optics were aged even when Orion was young. And yet they held a life to them that was undeniable. Passion incapable of being smothered by the harsh words of others and the seemingly impossible trial that was going up a caste. Ratchet bore every burden and political scheme with blunt determination, his optics always shining brightly as a hint of a smirk played on his features. Optimus loved that mischievous grin and the telltale glint that Ratchet got in his optics when he had some wild plan cooked up. Even though he was unable to bring himself to utter the compliments that formed in the back of his mind, he loved the Doctor's optics more than he cared to admit. So much energy contained within a compact frame. It was beautiful in its own unique way.
Once the war began and Orion Pax became Optimus Prime, he did not think about Ratchet's optics as much. At least until they began to lose the shine that he had been so familiar with in his youth.
War was uncaring, and it held no love for those trapped within its web. Optimus endured it with the patience of the old gods of Cybertron long since left to rot. Whispers of ancient beings far beyond his comprehension clouded his sense of time. Tears he wept for the fallen turned his gaze away from those around him and instead to the rivers of energon that flowed around his pedes. He endured it as the last of a long line of divines given frame. But Ratchet was mortal, and as the war dragged on, those optics that Optimus adored grew darker. Passion changed to red hot fury so bright and dangerous that Ratchet's gaze felt almost like venom at times.
Stokes of fire leapt through Ratchet's blazing optics, and more than once, Optimus feared he'd be scorched by that boiling inferno of loss and grief. And yet despite being the one to lead their war ever onward, Optimus never felt Ratchet's anger directed at him. When those optics gazed up at him, Optimus felt only age old affection and care. Fire was tamed and turned to comforting warmth. Steady servos ran along his arms, and a soothing voice lulled Optimus into temporary serenity on long cycles where he simply had no more tears to shed or reason to give to their Primus forsaken war. All the while, those optics met his own, and Optimus was at peace.
Vorns passed by. Optimus continued in his eternal march toward victory, and Ratchet continued to change. Rage turned into bitterness, the molten hot wrath of war transforming into a deep set sorrow that left creases in the living metal that surrounded Ratchet's optics. Grim darkness pooled in that once passionate gaze. Those optics flickered in wrath long fostered each time Megatron made himself known. Those optics flared with every injury that the team brought with them back to base once they arrived on Earth. Those optics that Optimus loved so dearly dimmed and quieted, their light softening in the dark of the medical bay on long nights when Ratchet thought no one would hear his quiet sobs.
Optimus always loved Ratchet's optics.
He should have treated him better.
"Does it still hurt?" Optimus asked as he ran his digits over the weld on Ratchet's side.
"Of course it does. The weld has only been in place for a month, and the wound ran deep." Ratchet replied clinically, not looking up from his work even as Optimus risked wrapping his arms around the doctor's waist. Others could see, but in the moment, he didn't care.
"I'm sorry." He murmured into the crook of Ratchet's neck as he leaned down, desperate to feel the comforting warmth of Ratchet's frame against his. The Doctor stilled, his field extending and wrapping around Optimus with concern.
"Optimus, please, we've talked about this. I was out of line in saying that. You are not at fault." Ratchet broke from Optimus's embrace and turned around. Optimus wanted to look away in shame as those optics looked up at him, still as lovely as ever, but tinted a haunting green.
A sign of Optimus's greatest failure.
"I am at fault, and you know that as well as I do. Let us not delude ourselves." Optimus reached out to cup Ratchet's face. The Doctor leaned into his touch obligingly. Any open affection was a risk, but there was something unspoken that needed to be addressed before time ran out and the world drew them apart yet again.
"You have always done what you think is right. I can't blame you for hoping and trying to save a mech who was once a friend." Ratchet's optics cycled, and the green became more prominent within them in response to his emotions. Optimus frowned and shifted, caressing the metal around the Doctors optics. His scarred digits traced creases and small scuffs, lingering around the corners of Ratchet's optics as Optimus observed the green hue in sorrow.
"You shouldn't have felt pressured to do this to yourself. The risks were too great. If I had only-" A digit pressed to Optimus's derma before he could continue, silencing his attempts at being self deprecating before they could truly begin.
"I made my choice. It is not your fault. Besides, the world is just a little more green for me now. That is all." Ratchet forced a smile, but Optimus could not bring himself to do the same. Ratchet's words while he was on synthetic energon were cruel... but undeniably true. How many times had Optimus had the chance to bring down Megatron only to let the warlord go? How many lives could he have saved if he had only put aside his feelings on the matter and acted?
"I can tell you are beating yourself up over it. Stop. It's over now, and I'm fine." Ratchet pulled away, and Optimus's servos fell. They stood quietly together for a nanoklik before Ratchet moved forward, his smaller frame pressing against Optimus's in a gentle embrace. Strong arms hooked themselves around the crooks of Optimus's torso, unwavering but gentle enough that if he wished, the Prime could pull away.
"Forgive me." Optimus murmured in the quiet of the medical bay. A gentle hum met his plea. Neither said another word as they stood in the relative darkness, comforted in the presence of one another. Only the light of the nearby console lit up the area, but it was more than enough for the Prime to work with.
Green-tinted optics glowed in the gloom, illuminating Optimus's face as he leaned down. Ratchet's optics closed, most likely expecting a gentle touch to the crest of his helm. Instead, Optimus leaned as close as he was able, even going so far as to angle his helm so that he could get near enough to place a ghost of a kiss over Ratchet's optics. Each closed optic received the lightest of touches, so soft that it may as well have been a gust of wind. But as Optimus pulled back and settled into the helm touch that Ratchet had likely been prepared for, the Prime finally smiled.
"Thank you for standing by my side." Ratchet stared in shock as the Prime's digits again found their place, tracing around the Doctor's optics. Ratchet stood still, uncertain of how to respond, until Optimus spoke again.
"I've always loved your optics, regardless of their hue." Optimus assured himself, earning a gentle huff from his companion.
"You sap." Ratchet whispered even as his optics glowed in all-too-rare joy at the show of affection. The green was still present, a permanent reminder of the costs of war. However, Optimus continued to smile all the same, simply pleased to have those optics locked on him.
Yes, Optimus would admit it aloud if times permitted.
He had always loved Ratchet's optics.