She's his addiction.
He couldn't keep his hands off her even if he tried. Not that he's ever wanted to. He's always admired the female form, has always enthusiastically carried on his family's tradition of lechery (if he was going to bear the punishment for it he might as well enjoy the crime, right?), and she embodies everything he loves in women: their beauty, their strength, their blend of femininity and capability, their intelligence… even if he has forsaken these qualities for a quick sating of lust in the past.
It's funny, how she's affected his lechery so profoundly. Before he'd met her, if someone had told Miroku that he'd one day fix his attentions on one woman he'd have laughed in their face… and gone off to drink sake and chase skirts. If they'd told him he'd fall in love, that he'd ask a woman to bear him a child only after Naraku was defeated, he might have lost his patience- probably the one monkly attribute he actually, genuinely possesses- rapped them with his staff as he so often does Inuyasha, and been upset with himself for letting a woman so close when his life would (most likely) be cut short. Very short…
Odd how she's also affected his view of the Kazaana.
Is there any part of him she hasn't infiltrated? No matter how far his thoughts stray, they always come back to her; his heart is hers, no question. He has thrown his body between Sango and death time and time again, and made it clear that it's hers should she ever want to claim it. She has rocked him to his core.
He can't stop watching her; can't stop thinking of her; can't stop touching her. She's everything he's ever wanted and never dared to think he could have, and sometimes he doubts that someone like her could ever want someone like him.
Sango could marry a lord; a handsome, rich one at that, who is in love with her- who has been in love with her for years, who has pledged to wait for her. Miroku has nothing to offer but his love and support, and amazingly, it seems to be enough. He might not have been able to understand this if he hadn't felt the same way; no matter how beautiful and strong and noble the lady, none of them could measure up to Sango for him.
Which wasn't to say that he hadn't slipped into his old habits now and then. Patterns of behavior, especially inherited ones, were extremely hard to break, and Miroku would be lying if he said that he didn't notice pretty women, or lust after them, and he knows how it hurts her. But he would also be lying if he said that they didn't come up short when he compared them to Sango, as he inevitably did, or that he'd slept with any of them since meeting her.
Though some- all right, most- of that could be better attributed to circumstances than his self- control.
Miroku grinned and looked at the subject of his thoughts; feeling his gaze on her, Sango looked up, blushed at his expression, and dropped her gaze to Kirara.
Stifling a laugh the houshi closed his eyes and lifted his face to the stars, basking in the warmth she gave him.