Vincent didn't, as a rule, let his arm get damaged on purpose. It was just difficult, without proper pain sensors or a degree in mechanical engineering, to know when something was going wrong. He wasn't familiar enough with the limb or with machinery in general to be able to pick out the meaning behind the different pitches of whines, grates, and clanks. Instead, he read them secondhand, translated through the tension in Cid's shoulders, the twitches of annoyance on his face.
In the end, Cid stomped into his room one night with his tool belt slung over his shoulder, a cigarette clamped in his teeth, a steely look of determination in his eye, and a bottle of whiskey in his hand. He thumped the bottle down on the table right next to the rag that Vincent had used to clean his gun and said, "All right, goddammit. Let me see it. I swear I'll put it back together good as new, but that grinding is driving me fucking nuts."
Vincent breathed in and out, once each. There was no sense in refusing. The malfunction was bad enough that he could feel it in lagging response and in jerky, incomplete movements.
Vincent holstered his gun, pulled back his cloak, and laid his arm on the table with a clank. Cid frowned as the claws chose just that minute to spasm. "Fucking hell. Glad I brought my heavy gloves." He dragged over another chair, adjusted the placement of the lamp, and settled down to work.
Vincent watched, at first. Cid found the hinges of the outer plates easily enough, folding them up to get at the machinery underneath. Once, he hit something electrical, and Vincent's claws spasmed hard, digging into the wood of the table and slicing the heavy leather of Cid's gloves.
The detachment, the almost-vertigo, the feeling of unreality, started then.
When Cid started taking the outer plates off completely to get at some delicate mechanism buried within, Vincent looked away. When he felt his arm grow lighter, then lighter still, as layers of the metal were lifted away, he reached for Cid's cigarette pack, lighting another for Cid and then one for himself.
When he made the mistake of looking down again, at the bulk of his limb (robotic and WRONG it might be, but still his) turned to a bare bundle of wires and a two-inch lattice of metalwork, when his perception switched from "my arm is metal" to "my arm is not there", Vincent reached for the bottle.
Cid hadn't touched it. By the way he didn't say a word while Vincent held it between his knees to twist the cap off, Vincent realized that it'd been for him all along. He was going to have to give the pilot credit for more than just his technical aptitude and broad cursing vocabulary.
Cid pulled his hands away, lit a cigarette for himself, lit one for Vincent, and put his gloves back on. "You know, this reminds me of one time back in the war when we crashed in the hills around Tan Dehnan and I had to fix the goddamn rotor actuator with...did I tell you this one?"
He might have. Most of Cid's stories had to do with having to fix something. Vincent shook his head.
He drank and smoked and concentrated on Cid's long, rambling, jargon-filled story until he had an arm again.