As soon as you went entirely through the gate, you were tainted. Edward knew that, now that he'd been to the alter world and back.
He had only become more tainted when Envy had killed him. He could feel it while he was standing there, in front of the Gate. The large, engraved eye at the top captivated him and he couldn't bring himself to feel anything.
Then there had been an incredible pain in his chest. The pain broke into his numb mind and unfeeling body. It had made him break his gaze and turn around. Edward's eye widened as he recognized the form standing before him.
"Al…" He said just barely below a whisper. It was more of his lips moving, but it sounded like a scream in the nothingness in the Gate's plane of existence. He could do nothing as he watched Al's body fade and disappear. It was then that he realized what the pain in his chest was.
It was his heart. His heart, which was laboring to pump stilled blood with out oxygen. He closed his eyes to do what he didn't know. But it made the pain dull slightly. When he opened them again, he didn't see the nothingness outside the Gate, but an intricately worked ceiling.
He felt streaks of wetness trailing down the sides of his face. He brought up his right hand to wipe the wetness away. Only to be surprised at the contact of soft, warm skin instead of cold, hard metal. He pulled his hand away in shock and sat up. His head swan a little at the abrupt motion, but he ignored it as he felt his left leg. It, too, was soft and warm.
There was someone else in the room. He vaguely remembered her. Rose, he thought her name was. He told her to leave this place-although he really couldn't remember just what or where this place was.
After she left, he moved slowly. He removed his outer shirt and the thin tank top and just looked. He couldn't believe it. His arm was really back. But it looked…wrong. No, not wrong. Different.
And then he realized why. The time he had spent in front of and actually in the Gate. Nothing can get near that thing and come away the same. He wasn't entirely human anymore.
He stood on slightly unsteady legs and looked around. Clapping his hands, he created a transmutation circle on the floor. He then transmuted a crude stone knife. He made a cut on his hand and, in his own blood, drew another transmutation circle on his chest, arms, and forehead.
He looked around one last time, sighed, closed his eyes, and activated the arrays. His last thought before going through the Gate and-somehow he knew-leaving this world forever was 'Al, I'm sorry. I never told you "I love you."'