Kimblee likes people who are sincere in their beliefs, which predisposes him to like soldiers in the first place (and he gets on so well with soldiers, just ask him): a female soldier must have worked doubly hard to be where she is, and be doubly devoted to her job or her duty, so for him, a woman in uniform is doubly entertaining, interesting, and enticing.
It irritates him on the Ishbal campaign when he first meets the 'Hawk's Eye', and finds that she prefers camouflage gear to more formal uniform. It's not exactly offense – he's too sensible for that – but it is a note of purely aesthetic irritation, the sort of thing that drives him to wear white rather than black or camouflage himself. There should be, he feels, more edges. More precision. More . . . metal.
He'd like to see her clothing echoing the steel in her eyes. It's philosophical, true, but that's always been his true lust, his private requirement for aesthetics. Her sniper's gear is aggressively plain, her cape is clean but ragged, and her gaze is shielded, constrained, enslaved in loyalty. A rifle rather than a pistol or a sword: delightful in her precision and aim, of the very best steel.
He makes excuses every now and again – not enough to alarm her or her commanding officer, he wouldn't want to frighten this dog away from his hand – to be present at meetings that she'll have to attend, just so he can see her in full uniform. Crisply pressed edges. Bright metal on shoulders and sleeves. Tightly combed hair. Hard sharp eyes, lips closed shut over opinions and secrets.
He even takes the opportunity to probe a little, to console her and her Flame Alchemist one time, reminding them of their duty, their honour, their obligations. The pure rage in her eyes as she looks at him before turning away sparks a little responding flutter in his hands, a precursor to explosions. She is beautiful in her control, and beautiful in her anger: if there were any justice, she would smell of hot iron, a mingled lure and warning.
Sun to moon, male to female, light to darkness, fire to water, all good alchemical pairings: but surely one of the best of them, and one which never turned up in the alchemy books, was a beautiful woman in the severity of an army uniform.