She's just like a flower hurricane.
He laughs when she tells him the name of some of her attacks. He managed to keep a straight face for 'coconut cyclone' (though really, no one could blame him for finding that funny), but he can't hold it in for 'flower hurricane.' It fits her so well that it strikes him silly. She of course sees no humor in it at all. She darkens and punches him in the arm, leaving it sore for days, and swears at him so thoroughly it makes Zoisite turn purple. That's the hurricane.
The flower is the look in her eyes, not at all enraged. Just hurt, as if he had run her through with his blade and all he's done is laugh.
He admires her for it, having the ability to have hard edges and that softer side. She appeals to him above Mars's sharpness, Mercury's quiet, and Venus's... Venusianness. She's both sides of the coin, yin and yang, rough but not course, soft but not weak.
He's never met a woman like that before.
He's not ready to marry her of course. That's just madness. He's not even fully inclined to go to bed with her, though such a thing would be mad in an entirely different way. He's just intrigued by her, wants to know more about her. He doesn't acknowledge that he can't stop wanting to know about her and that he has always liked brunettes and bright green eyes.
After much consideration (and an order from Endymion), Nephrite stands at her door, ready to apologize for his behavior. He is poised, knowing that he is venturing into no man's land, aware that he is quite possibly the only man alive both stupid enough to incur her wrath and apologize for it afterwards.
He knocks bravely, ready to be taken the storm.