Disclaimer: FMA isn't mine.
Song: This Week The Trend - Relient K
He could go from being an optimist to being a pessimist in the blink of an eye.
She was always a realist.
He could be so inspired and filled with fire as to think he could change the world, then turn around and wonder why he thought he could make a difference.
She always believed in him, even when he himself didn't.
He could throw caution to the wind because there was a possibility she might be hurt, then yell at her for taking too many risks.
She did what she had to do to keep him safe, bearing his objections in silence.
He would flirt with every skirt clad figure in sight, then look at her and wonder why the woman he really wanted was the one he couldn't have.
She was a steady presence at his side.
He would use alchemy to heat his tea and zap bugs from the air one day. The next he would say he was never going to use alchemy again because it had caused the deaths of too many people.
She never faltered when she pulled the trigger, and hit the target every time.
He chided Edward for showing a blatant disregard for the rules, then twisted them to suit his own purposes.
She was his voice of reason.
He was like fire - he constantly shifted from merely flickering to a full fledged flame and back.
She just was.