It was the giggling that should have alerted him. Unfortunately, in Sokka's mad dash to complete an important document, the small but revealing action of laughter went completely over his head for several minutes.
That is, until he realised Toph, of all people, had made said noise.
Frowning slightly, he moved away from his desk and rubbed his eyes. Looking out the window as he passed it, his eyes widened as he realised how late it had become. He would have groaned, however another bout of laughter brought him back to the moment, and he remembered why he had stood up in the first place.
Walking to Toph's room, he heard a low moan. Not the painful kind, but a different, a more pleasant but less innocent one. He cleared his throat and opened the door.
To say that he was shocked to find her with another person would have been a severe understatement.
His breath caught as he stood silently in the doorway. He could see her hair, cascading like a midnight waterfall down her back and over her shoulders - unclothed, enough to suggest that she was shirtless. And with Toph, it was entirely possible. That wasn't even the worst of it.
She was sitting - no, straddling - her make-out partner on her bed, feet off the floor. He had never seen her use the furniture before, the floor being made of stone; watching her enjoy being blind (and by the noises she made, she certainly was enjoying it) was a completely foreign experience for him.
She was clutching the face of whoever she was kissing, and the boy was holding her hips with a passion Sokka didn't want to think about. With his hands running up and down her shirtless sides (it was quite obvious now that she was in nothing but her pants and bindings) and their bodies far closer than Sokka deemed appropriate, the Water Tribe boy could do nothing but stare. It was due to sheer shock at watching her probe the face of a young man, lapping at him almost greedily, that had stopped Sokka from going over there and punching the daylights out of whoever deemed himself good enough for his friend.
Startled out of his highly inappropriate staring when Toph uttered a low moan, he realised that they had no idea he was there. Shouting out, "What the hell are you doing?", he felt a small stab of satisfaction as Toph jumped away, falling over backwards and landing on the ground with a loud "Oof!"
"Sokka?!" Her voice would have been a screech had she been capable of such a noise. Instead, she sounded like an extremely upset, extremely pissed off sabre-tooth moose-lion. Standing up, Toph marched over to Sokka, glaring angrily.
"What are you doing, kissing a boy?! You're too young for that!"
If possible, Toph's frown became deeper, and she snarled at the Water Tribe boy, "You were doing worse things than that to Suki at my age. I'm sixteen, I can kiss whoever I want. Get out."
She turned around and made her way back to the bed, and Sokka finally got a look at the boy she had been kissing.
He was probably the same age as Toph, with a strong jawline and impressive abs that Sokka glared at until Toph's lithe fingers began running up and down his chest, covering them.
"Close the door on your way out," she called before leaning down, capturing the stranger's lips with her own.
"No. This is my house too, and you," he pointed to the boy, "get out."
"No, stay; it's nicer here." Sokka had never realised how seductive and dangerous Toph could sound at the same time. Making an executive decision, Sokka walked over to Toph and plucked her off the boy, narrowly avoiding her writhing limbs as she fought against him.
Holding her away from the floor, it was obvious as the girl ran out of energy from fighting Sokka that the boy wouldn't get what he wanted from her, and quickly left after that. As Sokka heard the front door click, he put Toph down, who immediately swung around and sucker-punched him in the jaw.
"What the hell was that?!" she cried at him, pure rage boiling to the surface. It was times like these that Sokka was grateful she wasn't a firebender.
"Ow... Whaddya mean?" he asked, rubbing his aching jaw.
"What do you mean, 'whaddya mean'? What. The hell. Was that?"
Sokka cowered slightly under her glare, before realising that he was a man, and men do not cower. He pulled himself up to his full height, an impressive six feet that would possibly have intimidated Toph had she been able to see it.
"You're too young to be doing things like that. It's disgusting, men only want a quick shag, then leave." Toph let out a humourless laugh that could almost have been considered a cackle.
"What, like what you did when Suki dumped you? Oh, yeah. I heard, Sokka. Hell, I felt it. I can definitely tell what disgusting is."
Sokka completely ignored the hypocrisy of the situation, instead plowing ahead as though he had planned the speech.
"It doesn't matter. I know you can protect yourself, but I still don't want to see you get hurt..." He trailed off, not looking at her. Finally dragging his eyes up, he realised with a shock that she was blushing. The weight of the conversation suddenly dawned on him.
I walked in on her about to have sex with someone!
Unable to continue talking to her after such an epiphany, he mumbled a quick excuse and left, allowing the door to her room slam shut behind him. He thought he heard her say something, but quickly dismissed it, not wanting to face her.
"Why do you care so much, Sokka?"