Spoilers: Erm... Envy?
Warnings: Character death.
The cat looked up at him curiously, its head cocked to one side. Its fur was dark grey - perhaps it was normally lighter, but the rain had darkened it - with black stripes running through it. It shivered and meowed pitifully, soaked to the bone. It didn't look used to life on the streets at all; more like a house cat that had been thrown out of its home.
Al looked around quickly, almost guiltily. Good - his brother wasn't around. He knelt and removed the head of his armor, scooped up the cat and tipped it in in one fluid, practiced motion. Unlike most cats, this one seemed not to mind the darkness inside the suit of armor. It purred happily and settled down, seeming to enjoy the respite from the pouring rain.
"You'll have to be quiet... My brother will throw you out if he knows you're there," Al said to the cat, and was pleasantly surprised as it meowed back at him, almost as if it understood. If he could have, Al would have smiled. "Hey, you're pretty smart, for a cat."
Al tiptoed into the room he and Edward shared, although more often than not it was empty, as the Elric brothers traveled across the country in search for the Philosopher's Stone. He walked over to his bed and sat down, looking down at his chest. "You know, you can't stay in there forever. Brother will find out sooner or later, and then I'll have to let you go." He looked out the window, noting that the rain hadn't stopped and it didn't look like it would any time soon. "I guess after the rain sto-"
"You know, for someone who's supposed to be a genius, you're pretty damn stupid," a voice said from inside him, silky smooth and cruel as a razor. Al froze as he felt claws that seemed much too sharp to be those of any normal cat dig into the metal beside his blood array. Realization slammed into him like a pail of ice water and he gasped, trying to get up, removing his chest plate-
"So long," the cat that wasn't a cat said, cheerfully. Its claws scratched viciously sideways, and Alphonse's world went dark.
Edward Elric staggered into his room and flopped bonelessly facedown onto his cot, not even bothering to remove his red jacket. He turned over, his eyes closed.
"You won't believe what Mustang had me doing all day, Al," he said wearily. "Honestly, cleaning the toilets? Do I look like a janitor to you?" A fraction of a moment passed in silence. It was too long.
Edward sat up and opened his eyes, looking over at his brother. Al sat on his own cot silently, not commenting on how Edward and Colonel Mustang should try to get along, not saying that Edward should have told that to the Colonel in the first place... not saying anything at all.
"Hey... Al?" Edward got up and walked over, putting a hand on the armor's shoulder and shaking gently. "Al?" His voice started to shake as Al didn't reply, and the tiniest hints of panic seeped into his amber eyes. "Al? Stop playing around!" he shouted, suddenly angry; angry was better than frightened, better than anything but-
Shaken too hard, the head of Al's armor came off and fell to the ground, clanging noisily on the wooden floor. Wide golden eyes focused on the array that kept Al's soul affixed to his armor... Three deep grooves scored the metal, raking through the array and ruining it entirely.
Envy's ability to change into pretty much anything - as showcased in the manga - has the evilest possibilities.