You're startled and momentarily alarmed when you realize that your perception of her has changed. After a couple of rounds of hyperventilation you sort of resign to the fact that this has probably been building up inside of you for quite some time. She has always been part of your life, after all; you know pretty much everything, good and bad, there is to know about one another, and the fact that she puts up with your moody bullshit in spite of that is testament to (at least) two things, being a) You've been a blind dumbass, and b) You couldn't ever possibly even hope to deserve her.
In your most secret, would never-fucking-tell-anyone dreams you're very suave in your approach, and she swoons at your proclamations of love and wanting to bone (stated in albeit less blunt terms by your apparently debonair alter-ego), and insists, naturally, that you have your way with her. (There's no riding off into the sunset in these fantasies, but there is an exceptional amount of boobs.) In real life, though, the thought of grabbing her hand out of context sort of makes you want to vomit (out of fear of wrenches, mostly), and from that first consideration onward pretty much any thought of her, and in any capacity, is enough to send you into fits of anxiety for about two years straight.
That doesn't stop you from thinking about her, and what could, really? She's brain-aneurysm-inductively amazing in every way and then some, seeping into and making her mark in every corner of your life; even when you're running for it your conscience takes her form and calls you a suicidal alchemy freak. Beyond that, everyone else you interact with can be counted on to attribute any momentary bouts of insanity to you being the 'Fullmetal Shithead', the dicks. Thinking and panicking does, however, bring to light just how honestly frustrating it is to travel constantly with someone who never sleeps. Dirty thoughts turn into lovey dovey thoughts turn into dirty thoughts, and you find yourself coveting precious, solo moments in private rooms and showers. They're few and far between, and your resolve wears pretty thin everywhere else, yay hormones. Still, you don't want to embarrass either yourself or your brother. Or her, for that matter, because who knows what comes out of your mouth when you're in the middle of it.
Time starts to seem both stale and rushed. She continues to amaze you, with the depth of her passions, her unquestionable skills and ingenuity, and with her unshakable loyalty. You become convinced that no other woman in the world can even see the bar she's set, let alone surpass it. As her intellect grows, her skirts seem to get shorter. Her always bright smile makes you inexplicably confused, and perhaps irrationally committed to eliciting it as often as you possibly can. She wears her heart on her tube top. Both her happiness and her sadness are infectious. Her laughter makes you feel invincible, and her tears make you destructive; you're angry at yourself, angry at the world, angry at everything. The audacity of the universe in allowing her to cry makes you clench fists and bare teeth, and you make mental notes to punch the shit out of the Truth if you're ever at the gate again.
You don't think she's aware of the effect she has on people, on you in particular, and you're tempted several times to tell her that if she ever decides to make a bid for the Fuhrer's seat you'll happily push Colonel Bastard off a cliff. You're mesmerized by the aura surrounding her, because there's no one else like her in the entire damn world, and one day as you're walking behind her (hypnotized by her sashaying ass and musing about tasting her thighs, probably), you mutter out loud that if she jumped off a bridge you'd be half a leap behind her. She doesn't hear you, but your brother does. He is tactful enough to smirk (so much as a suit of armor can) in silence.
When you see her again before the Promised Day (after your frozen, gawking, idiot face has regained some semblance of composure from the shock of her half-undressing in front of you) you decide that, if you manage not to die and/or the world doesn't end, you're going to marry her. Not against her will or anything! If she'll have you, you mean. You sort of maybe get the feeling that she will. Maybe. If the planets align, and the stars are having a good day, and if you're not your usual foot-in-mouth, word vomiting self. If you're horseshoe-up-the-ass lucky and can find your balls long enough to squeeze out the words between heart palpitations, you completely hopeless nonce.
When it's all said and done, and you're home again, your courage rolls in and out like waves. You're both trying, that much is obvious (to the amusement of the Old Bat and your sly-eyed little brother), and you both have no idea what to do now that nobody needs saving, or fixing, or prioritizing. You keep catching eyes and blushing, and then suddenly having important tasks that need immediate attention, both desperately trying to pass off your pathetic excuses as anything but avoidance tactics.
Your brother comments that you both seem afraid of one another, but you think it's probably more fear of a very substantial change in The Way Things Work.
The Right Moment is elusive and seemingly non-existent, and so one day, out of some exhausted combination of blind lust and internal animosity, you just sort of grab her as she's coming around a corner. Your mouth feels dry, and you think that the odds of you saying something stupid are like, 10/1, because she is inches away from you (though your confidence is temporarily boosted by how you are, clearly, taller than she is HA), startled and wide-eyed, with all escape routes effectively cut off.
"Uh. Hi." Smooth.
The colour rises in her cheeks and you immediately feel the heat in your own face reciprocating. "H-hi."
"I, um. I've been thinking-" You've got a hand on each of her arms, and you're afraid that if you let go, she'll flee, and you'll be a loveless, virginal dipshit forever. "Or, uh. Heh. I've been trying to, er..." Spit this out, for the love of God, and kiss your siren-song-singing mouth! "You know, uh." You pause, lost, and sort of stare at her, because apparently you've forgotten how to speak English. Dully and repeatedly you berate yourself: moron, moron, moron.
"What?" she asks, quietly, shyly. Her body is tense but her eyes seem both invigoratingly and terrifyingly hopeful.
How is every man in Amestris not fighting for a second of her time?
"Fuck it," you answer, and crash your mouth into hers.
Eggs in one basket and feeling like you're facing the executioner, you're concentrating so hard you start to wonder if it's anatomically possible for your eyebrows to furrow themselves into your nasal passage. You suddenly understand why love makes people behave like totally fatuous mooks. Both your elation and fear are intoxicating. She tastes like coffee, and smells like grease and sweat and flowers. She rests a tentative, delicate hand on your chest before enthusiastically reciprocating your attack.
You're not sure how long the two of you stand there, but the kissing melts from confused aggression to eager exploration. At some point your hands find your way to her waist, her arms slide around your neck, and together you close what little distance is left between you. When you finally break apart you're both gasping for air, though breathing seems an incredible inconvenience to the necessity of continuing kissing, of kissing her forever.
When you open your eyes she's looking at you with a new expression that takes a moment's processing. When it clicks it's because you recognize it in yourself: It's want. This thrills you to new extremes. Your foreheads are touching, her breasts are pressed against your chest, and you can already feel your pants getting tighter. You want to demonstrate to her every single emotion that you're feeling, but you haven't got the sweetest clue in the damn world how. Holy hell do you ever want to figure it out.
"Winry," you manage, a broken, desperate record.
"Ed?" she questions, like someone coming out of a haze.
"You- you know I love you, right?"
Her breath hitches as she ducks her head and nods, her palms flattening on the back of your neck. "Y-yeah. Me too." She looks up at you again, smiling shyly, and you break out your best shit-eating grin in return.
In an instance the tone of the moment changes and she's kissing you again, all ferocity and determination, catching you off guard as she shoves you with surprising force into the opposite wall. "Now, shut up, you idiot," she mumbles happily into your mouth. You internally salute with gusto, in love and horny and whatever else, the scientific side of you tickled pink to discover that happiness and sadness aren't your wonderful woman's only persuasive emotional extremes.