Written post-manga #237, pre-time jump. I make no claim to the characters, etc.
Summary, in short: He's out of his mind and she's rockin' some serious codependency issues.
Periodic edits because old!me has some feelings about young!me's narrative tics & tendencies—which translates to some rewording, some clarifications, and the removal of hundreds of extraneous instances of the word "that." :P

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If he hadn't shifted at that exact moment, Sakura would have walked straight past him. As it was she only slowed, sparing him a glance, before deciding she at least owed the Sand ninja her thanks.

Her halt, her consideration, and her approach were all met by the same dispassionate stare. Gaara didn't move from where he leaned against the wall, didn't blink once, watching her until she was certain he only did it to make her uncomfortable.

Sure of this, she refused to look away from him. The clench of her jaw brought his first response—a smirk.

His eyes were still damned unpleasant, she noted. But the markings around them . . . Naruto had told her about their once-adversary, about his self-induced insomnia. The level of self-control, of willpower necessary to deny such a basic need was completely beyond her.

The twist of his mouth made her aware she'd been staring silently, and had done so for long enough to warrant his next response. "Well," he said. "You want something?"

"I wanted to thank you for saving Lee."

The expression deepened as his chin lowered, his irritation becoming more prevalent. "It was an order."

"But still—"

"It was an order." His lips slid back from his teeth.

It seemed his sentiments were infectious. The way he looked away from her again, as if dismissing her so easily . . . Her fists clenched, then relaxed. No, she wouldn't lose patience. Not over something like him. "I talked to Lee already. You could have waited those extra seconds it would have taken for him to be killed, but you didn't. Your sand protected him."

His hands clenched as he unfolded his arms. His antipathy was perfect, complete. "Does it matter?"

"Yeah . . . Because you didn't let him die," she replied. The returning silence from this boy said it all—and as she truly realized the significance of his actions regarding Lee, she couldn't hold back a fleeting smile of satisfaction.

The ferocity in his responding glare told her she'd just made a mistake.

But no matter their past or whatever his mindset could be, he couldn't kill her. Sand and Leaf were allies again. Attacking her would destroy the truce, and he had to know it as well as she did. This certainty allowed her to give her spite free rein, encouraged her to step forward. The person in front of her had mercilessly caused Lee so much pain, had almost killed her Sasuke . . . But he couldn't harm her.

But if the way his weight and expression shifted were any indications he was suddenly wary of her, as though she'd also become one of his more trying opponents.

From him, that might be something of a compliment. And though her stomach clenched unpleasantly at her emerging plan, it wouldn't do for the Fifth Hokage's new apprentice to leave a potential advantage unexplored. Her steady progression towards him brought his head up, drew a question out of him with a low hiss: "What are you—"

"Thanking you."

"I don't want your thanks."

Barely thirteen years old and already one of the most monstrous killers she'd ever heard of. But he couldn't kill her.

Wild, wide green eyes and the faint glint of teeth marked his unease as he straightened. The loose grains of sand grazing along her skin as she stepped within arm's reach disclosed his agitation, but no hands solidified or lifted to otherwise stop her. If his expression was any indication, he . . . didn't know how to handle her?

Her cheeks heated momentarily as Lee's synopsis of the afternoon's events came back to her. No, he wasn't some crazed animal; just a person twisted by those around him until he didn't know how to deal with common society.

It was nearly impossible to hurt him; she'd seen that at the chuunin exams. However, he could be touched. She'd seen that, too.

All she had to do was get under his guard.

He couldn't kill her. Clutching that ideal as tightly as a child with a safety blanket, she reached out.

"It doesn't matter," she whispered. At her height, her chin fit perfectly over his shoulder as her arms went around him, her hands skimming against muscles stiff with surprise. Sakura realized with a shock how thin he was as his scapulae dug into her forearms. Had the inhuman power she remembered come from this small form?

Her response came as he finally moved, his hands rising almost sluggishly. Ready to be pushed away, she loosened her grasp . . . only to feel his sleeves brush her sides before he locked onto her in a vicious approximation of an embrace. Taut muscles shook as his arms shifted to encircle her completely, leaving her to wonder when anyone had even attempted to hold him last.

She wasn't sure how long they stood there, as his shudders subsided, as their body heat mingled and she became familiar with his scent. Eventually, though, the near-painful grip loosened, and she was able to step away.

Gaara's expression was no longer hard or hateful as his hands traced down her retreating forearms and fell away. "You . . ."

She couldn't shake the feeling her spite had started something much more serious. "I've got to go."

The feeling manifested itself the next day. Sakura was a good student, a decent ninja. She didn't willingly seek out trouble. Trouble, instead, followed her to her front door and insulted her, her ninja skills and her lack of strength, elaborating and continuing until she expected him to start attacking the cut of her dress and how she wore her hair. Eventually, Gaara's derisive tone wore down her apprehension and provoked her into snapping back at him.

"If I'm so horrible and so awful, if you detest me this much, then why don't you find someone else to harass?"

Surprisingly, he smiled. It was like watching a snake smile.

No, she corrected herself. She'd seen a snake smile, right before he bit Sasuke and shredded her dream of a happy ninja team into the tatters of childish wishes. This was something different, yet no less disturbing.

A normal creature, she noted to herself, would have run after being cornered and petted. This one apparently felt the need to come back for more attention.

"You're the first girl to willingly stand up to me," Gaara said. "And you're one of the few that has stood up to me and lived."

"But now you expect me to let you to walk all over me, like . . ." She gesticulated frustratedly. "Like I'm some kind of doormat?"

"No."

"Then what am I supposed to do?"

He shrugged. If anything, her frustration seemed to amuse him more.

She grit her teeth and inhaled deeply, preparing to verbally tear into him, when she remembered his actions from the previous day: his near-panicked grip, his body shaking against hers. Those, coupled with earlier memories of being crushed by sand . . . She halted herself and forced another deep breath before responding, almost contritely. "Why me? Why not Naruto? He'll give you all the fight you want."

His smile faded and he blinked as if considering the implications of her words, as if he were suddenly searching for his own reasons. For a few seconds he was silent. Then came the answer, in clipped, brusque tones: "You remind me of someone."

With that, he turned on his heel and marched off, leaving her to contemplate the depths of his insanity, to wonder who she could possibly remind him of.