A/N: Sorry for forgetting about this again. Here's a really long one-shot to make up for the absence.

OOO

Day 16: Lost

…

College AU Part 3

OOO

"Aang. The letters and numbers are literally moving around on the page. I think it's turning into Japanese or some crap."

Aang sighed over the phone. "You know, for someone who supposedly hates girls that are too dramatic, you really know how to exaggerate!"

"Okay, but that's the thing," Toph exclaimed, squinting at her problem set while she kept Aang on speaker. "I'm not exaggerating. This paper is literally in Japanese."

"No it's not," Aang deadpanned. "It's just a Calc III problem set. I know. I'm in your discussion section."

"Ok, but it still doesn't make sense! Ask Katara! She's got the easy professor and even she's confused."

Katara was sitting on her bed across from Toph and was chewing on the end of her pen. She called across the room so that Aang could hear her. "She's right Aang, this is kind of hopeless. We're both totally lost."

"Well that's what you get for missing lecture this week. The problem set is literally a regurgitated version of what we went over."

Toph's jaw dropped. "Hey, I meant to go! But I was exhausted and I needed to sleep in so that I could stay alert for the rest of the day. Don't blame me for taking care of my health," she finished nobly.

"You were binge watching Netflix the night before. That's why you were tired the next morning."

Toph paused over the phone and Katara burst out laughing. "Oh man, he knows you too well."

The girl decided to do the intelligent thing and ignore that comment. "Can you please come over and help me with this? I'll swipe you into the dining halls for dinner for a week."

"Seriously?"

"Totally." She meant it. She was desperate. Besides, she knew that was a decent enough bribe. Aang always seemed to go through swipes quicker than she did. Something about him needing have three meals a day whereas Toph could get away with sleeping through breakfast, going to class, and grabbing lunch later. She had a huge excess that her boyfriend always envied her for.

Aang sighed through the phone, but Toph knew that he wouldn't refuse. "Alright, alright. I just left the gym, but I'm coming. Give me ten minutes."

Toph cheered into the phone and fell back onto her pillows. "You're the best, Twinkle Toes!"

"I know. Feel free to stroke my ego more when I get there, okay?"

"Shut up," Toph admonished through her smiles before she hung up her phone. Perfect. No need to worry. Aang would come over, look at this mess, translate it into perceivable English, and hopefully get through this in a couple of hours so she could actually go to sleep early for a change. Honestly, Calculus III was a requirement to get a degree that says you can build a bunch of buildings? Someone needed to explain that to her and quick.

Toph flipped down on her bed—figuring she might as well relax and stop looking at the problems until Aang showed up—and raised a brow when she saw Katara packing up her things.

"I thought you needed help on the set," Toph prompted.

Katara slung her messenger bag over her shoulder. "Nah, I'm gonna go ask Zuko. He's really good with this stuff too. Besides, I figure the two of us would appreciate some private "study time" with our respective boyfriends."

Uh oh. Katara did that wide-eyed, smirk thing when she said "study time." "What in the hell do you think I'm going to be doing in here?" Toph demanded.

"Oh come on!" Katara laughed. "Tell me that you're not totally going to take advantage of the fact that you're going to have Aang in your room practically all night."

"All night?"

Katara shrugged and slipped into her shoes. "Well, I know what I'm going to be doing once Zuko's done helping me." She ended the statement with a wink and Toph immediately felt her embarrassment flood through her chest.

"God, Sweetness!" she practically shouted. "This is so none of your business."

"Well it should be," Katara proclaimed haughtily, like she obviously had every right to the intimate details of her best friend's sex life. "You've been dating for months, I am your best friend, and I think that at some point I should be aware of these kinds of things especially since it also involves another good friend of mine. I mean I've been meaning to tell you about everything I do with Zuko because I honestly—"

"Jesus Christ Katara—"

"—wanted to know what you think about—what? I'm just saying!" she finished with a hand on her hip. "You don't have to be embarrassed about it. I just care about you two!"

Toph rolled over on her stomach and buried her face in her pillow. "Get out, Sugar Queen!"

"Okay, okay, I'm going." She raised her hands in surrender and opened the door to leave before she popped her head back around the corner. "Just remember to use protect—"

"Get the hell out!"

Katara's cackles echoed down the hall and Toph didn't let out a sigh of relief until she stopped hearing the dull thumps of her heels against the carpet. That girl really knew the perfect way to get under Toph's skin. All of Katara's "let's be super open about sex" nonsense was at the top of the list. Ever since Toph didn't come back to the room for a solid two days, Katara grilled her until Toph admitted that she had been in Aang's room the whole time, and no one needed to explain to Katara what that meant. Ever since then, Katara wanted to know everything. Partly because she was a nosy friend, and partly because she knew it pissed off her roommate. Maybe it was a pre-med thing.

They were just studying tonight. Actually. Toph really couldn't get distracted tonight. No need to refer to the sex jokes.

There were three quick knocks against the door, and Toph couldn't help but groan. Not that Aang wasn't a complete joy to have around, but she really didn't want to stare at that damnable problem set again. She was just hoping that she picked up on missed material quickly because there was only so much stress that Toph could handle in one day.

She rolled off her bed and headed over to the door, grabbing her notebooks and papers and plopping them on her desk along the way. She yanked open the door and was prepared to reach up and give him a hug—

…oh fuck.

"Hey," Aang panted, looking like he ran all the way here. "Sorry, I didn't get a chance to change, I'm a little sweaty," he smiled sheepishly.

Normally that smile would look cute and adorable on the days when Aang was wearing hoodies, jeans, and sneakers. But right now, Toph was a little too distracted by the fact that Aang was sweaty and shirtless in her doorway, and probably didn't understand what an image of perfection he was giving off right now. Toph could only nod dumbly at him and step aside so that he could enter the room. Then her eyes widened again.

Damn, she never really appreciated his back before. But holy shit, his muscles were still flexing from after his workout and they looked like they had swelled a little too. Right, right, today was weight-training day. Aang still had his weight lifting gloves on and he didn't have his heart rate monitor on. She sort of remembered telling him that he didn't really need to bulk up anymore and that he looked fine the way he was, but suddenly that seemed like a seriously stupid thing to say.

Oh crap. Aang was saying something.

She blinked and shook her head a little. "Sorry, what?"

Aang innocently raised a brow. "I…said I was thirsty. Is it okay if I grab some water?"

"Uh…yeah, yeah! Go, um…ahem, go ahead."

Leave it to Aang to have no appreciation for the elements. It was November! It was practically 40 degrees outside and he was strutting about campus without a shirt on. How was he not cold? Wouldn't it just make more sense for him to put on a shirt instead of jogging all the way over here shirtless? She always told him this when he ventured out into a snowstorm grossly underdressed in just a pullover and a beanie while she was decked out like she was about to go skiing. Before it was funny and annoying in an endearing kind of way. Now it was just downright distracting.

Aang was eyeing her desk and picked up the problem set. His eyes scanned it quickly. "I think I did most of them myself already. They look bad, but the problems don't actually take that long to do. You just have to know how to set up the equations."

Toph nodded absently while Aang pulled out her desk chair and sat down. It wasn't like Toph had never seen Aang without any clothes on—that was kind of a requirement for sex—but it was different when Aang was strutting around completely oblivious to the kind of effect he was having, so she sort of had to pretend that she wasn't noticing either. It was like when Aang always mentioned to her all the looks she got from other guys and she had no idea she was even getting them.

She felt like a complete pervert just staring at him so openly, but where were her eyes supposed to go? His face? Kind of hard when there was so much skin gleaming just inches below. Was he actually expecting her to focus?

She shook her head. No. She wasn't going to do this. This was Aang: the same guy who laughed at cat gifs on Tumblr, jumped up and down whenever there were sweets in the dining hall, and still walked into poles and walls when he wasn't looking where he was going. Dorky. Quirky. Cute. Not hot. Not as long as he was in this room.

Right. Ok.

"Hey, what happened to Katara?" Aang asked. Crap, he was scratching at his pectorals. Wow, they were getting a lot more defined lately. "I thought she was having trouble with this stuff too."

Toph turned to pull out Katara's desk chair—quietly let out a tense sigh to clear her head while she was turned and he wasn't looking—and pulled it up across from Aang's. "Apparently Zuko's going to help her. Although I'm not sure how long that'll last."

"Yeah," Aang laughed, picking up a pencil off Toph's desk, already making marks on the assignment. "Katara never studies in Zuko's room."

Yup, and I'm not doing much better, Toph thought grudgingly.

No! Focus!

"Ok," Toph announced, more for her benefit than for Aang's. "The path of a particle in space is given by the functions, x(t) = 2t, y(t) = cos(t), and z(t) = sin(t). The temperature in the space is the function H(x, y, z). Find dH/dt."

"Did you start this one?"

"…is that supposed to be a trick question?"

"Alright, that's a no." Aang leaned back in the chair—oh, hello abs—and stretched his right arm across his chest—and hello biceps—as he looked up at the ceiling in thought. "Ok, well, dH/dt is just the rate of change of the temperature at the particle's position. And because we're not given the actual function H(x, y, z), you just have to give the answer in terms of derivatives of H. Make sense?"

Toph nodded, her eyes making prolonged eye contact with Aang's muscles as he stretched out his triceps. "Yeah…" she drawled out. She shook her head a little bit. "But that's going to be such a long answer. Is that ok?"

"Mmhm," Aang nodded as he dropped his arms. "Come here. Give me your notebook."

He leaned over and pulled her notebook from her lap, but Toph smelled the musk of the sweat still on his body still lingering and mixing with the cologne he must have put on this morning, and Toph had the strange urge to climb into Aang's lap, bury her face in the crook of his neck, inhale, and…

…wow. Ok.

Aang took a huge gulp of water—which then made Toph stare as his Adam's Apple bobbed as he swallowed, and really why was she staring at that, it wasn't erotic…or it was erotic, but it shouldn't have been and just, ugh—and started writing on the top line. "It's going to look gross afterwards, but you just have to use the chain rule. And it's good that you've got the sine and cosine in the problem because it's going to help you cancel things out and simplify."

Toph leaned over and saw that he had started writing out the chain rule for her, and stopped in the middle in order to let her work out the rest of the equation and just start canceling everything out and simplifying it. Now that Aang had started the problem, it seemed pretty simple to finish off, so she grabbed her notebook back and finished off the rest of the math, circling the answer and presenting it to Aang for approval.

"Great!" Aang smiled brightly. He leaned back in his chair and started absentmindedly fiddling with the drawstring to his exercise shorts. Holy hell, his hands were really close to something Toph probably shouldn't be showing prolonged eye contact with. Her eyes darted upward to his face as he spoke again. "You think you want to start the vector problem?"

Toph withered. "I tried starting that vector problem and I was just deriving these random equations that made no freaking sense," Toph whined. "Going through this whole set in one night isn't going to happen, I can't do this stuff that quickly."

Aang shrugged and conceded the point. "That's true. I feel like if you had more time to look at it, you'll be fine. The time limit is making you panic. But the good news is that you do have time."

Toph raised a brow. "No…I don't. That's the whole point of you coming here to help me, I have a limited amount of time."

But Aang just decided to laugh and lean back further in his chair with his hands behind his back, flexing more of his recently swelled muscles. "You really need to go to class."

"What are you going on about?" Toph asked in frustration and having long given up on hiding where her eyes were wandering.

Aang grinned impishly. "Well, if you went to class this week, you'd know that the problem set got pushed back to next week."

…and suddenly Toph got this terrible urge to slam her head against the desk, despite the deflating panic that was leaving her chest. "…are you serious?"

Aang nodded sagely. "Yup. Professor's travelling this week. Won't be able to grade them until next week so he pushed the due date back. Thank goodness too, because I have a paper due in a couple of days and I really—"

"Wait, wait, wait," Toph interrupted, putting her hand out to keep Aang from saying anything further. "If the problem set isn't due until next week, why didn't you say that over the phone? You came all the way here for nothing!"

Aang's relaxed and oblivious demeanor faltered for a little bit when he looked down at his knees and rubbed the back of his neck. "I mean, I didn't come here for nothing. You're here after all."

"Yeah, but you still could have told me the set wasn't even due. Why were you trying to get me to do it? While you're prancing around shirtless on top of everything else I mean, God!" Toph exclaimed, finally calling attention to the elephant in the room.

Aang grinned. "Why? I told you I was coming back from the gym. I didn't have time to change."

"Oh, don't give me that!" Toph nearly pouted in anger. "You can't possibly be unaware of the effect you're having."

"What kind of effect am I having?" Aang said with a wider smile as he leaned forward in his seat even more.

"Are you an idiot? You're—" and then Toph stopped in the middle of the tirade that she had already prepared in her head and then looked at Aang again. He didn't look like he was innocently unaware of himself any longer. If anything, that self-satisfied smirk on his face was something that she really wasn't used to seeing on him since he was usually an open book that was rather easy to read. But suddenly, here he was acting like he had known this huge secret that Toph hadn't figured out yet, and suddenly everything started to make sense.

She leaned over and slapped him on the shoulder. It was unclothed, so it made a nice loud sound that probably meant her slap stung. Good. "You underhanded jerk! You totally did this on purpose! You freaking tease!"

Aang couldn't help but break into a peal of laughter as he rubbed the spot where she slapped him. "To be fair," Aang said holding up his hand in surrender, "it was all Zuko's idea. I didn't think it would work, but he insisted that it was worth a shot, so I figured you calling about the problem set was a perfect excuse to try it out." He grinned devilishly. "And lo and behold it worked."

"No it didn't," she replied automatically.

"Oh, yes it did, you're frustrated, I can tell," Aang chuckled.

"No, I'm not," Toph insisted firmly. "I'm perfectly in control of myself. I'm not some hormonal Neanderthal."

Aang's fingers suddenly brushed gently up Toph's knee to the top of her thigh, and she visibly shivered in response.

She glared at him. "Stop that!"

"Not until you admit that it worked," Aang replied in a sing-songy voice while his hand had already spread out and cupped her knee as his fingers rubbed the sensitive skin on her inner thigh. Toph, stupidly enough, was definitely not trying to push his hands away to try and prove him wrong.

"Stop it!" Toph insisted with a small smile that she accidently let shine through. She shut her legs to keep his hand from wandering higher, but didn't bother to push his hand away.

Aang stuck out his lower lip, but used his hold on her knee to pull Toph and the wheeled chair closer to him until her knees knocked against the edge of his chair and she was settled conformably in between his own knees.

"Come on," Aang grinned. "Just say it. I mean, what's the alternative? Trying to do a problem set you don't understand that's not due for four more days?"

No, the thing to do would be to climb on top of Aang's chair and take full advantage of her roommate's absence. Thin walls and shitty soundproofing be damned. Toph tilted her head and scowled. "I don't know if I like this new Aang. He's getting all buff and over confident. Thinks that I want to take advantage of this situation."

"You like the muscles," Aang stated.

"Yeah, well remind me to come to your room on Friday in a thong and a garter belt and we'll see how you react."

Aang's blush stretched all the way to his ears and Toph really let out a delighted peal of laughter. All of tonight's confidence and male posturing aside, she still didn't forget the babbling fool that Aang turned into when he saw her in the lingerie she had bought for their first time. "…you don't have a garter belt," Aang said, shaking his head.

Toph merely shrugged, a little smug that she was starting to get the upper hand. She was never a fan of flimsy, lacy underwear or clothing, but she kind of liked the reaction she got from Aang whenever she did wear it, so the purchases were kind of worth it. "You don't know that. I could be wearing it right now."

Aang leaned forward and knocked his forehead with hers. "Well, I could be wearing the Calvin Klein briefs that you seem to like so much."

Toph bit her lip and Aang chuckled. Okay, so there was no point in denying that Aang shirtless was a downright delectable sight, right? Good, because that act was way too tiring to keep up. This was more fun. "Well," Toph ruminated. "There is an obvious solution for verifying all of this."

They both smiled at the same time, and Toph wasted no time climbing out of her chair and settling herself comfortably into Aang's lap, her arms already wrapped around his neck and her mouth already moving enthusiastically over his.