His master loved him. He knew that. He only wanted him to be strong, to be able to serve him to his fullest, and that was why he had to hurt- he had to temper himself beyond the steel, to be, at times, beaten into alignment, to make sure he could withstand the stresses a sword would have to. That was the only reason; it was because he loved him, cared for him so dearly, that he would raise his hand against him, that he would keep him from healing his wounds, that he would force him to withstand the blistering heat of the mountains, and force him under the surface of lake floria. Love was to be tempered, much like he himself was, from pain, and to be forged from the fires of passion, and cooled with a cold shoulder.
He couldn't wait for the day he would be in perfect form, to be worthy of being his sword. Even his hylian form- temporary, he'd assured Demise- was perfect, with a lithe form and smooth skin, and when his master first stroked his arm, he'd thought that perfection was sooner than he realised.
It was when he'd lain him against silk sheets that he was declared flawed, unworthy of the stains he'd placed on the fine fabric. He'd cried out and finished much too soon, he'd learned. He would have to train himself to have "some semblance of patience," and to "be silent, as a weapon should be," and he dedicated himself to the task thusly, wearing his bruises and limps with a swollen, bloated pride. He would go through any training for his master, no matter the amount of pain, he had promised him. He would grit his teeth and not cry out, not when being hit or scalded or when water filled him, incapable of drowning but an uncomfortable heaviness sinking in, regardless.
He would be perfect, someday, and it would all be worth it to see a smile on that grim face, or a pat-and not a slap- of encouragement, or just to be held, those warm hands on his cold steel. They would be perfect.