AN: Man, it's been a long time since I had a multiple chapter fic (I think the last one was about Wreck-it Ralph? So, it's been two years). I'll try to actually complete this one this time around; maybe I'll have fewer chapters so I can still have the groove of this story. So, I saw Big Hero 6 twice in the past two weeks, fell in love with it, and I had this fic idea that I couldn't resist writing! As always, if you have any sort of criticism, I would love to listen, I especially love helpful reviews! Anyway, let's get started! (I'm also really sorry if any of the character quotes sound OOC, I tried my best with what I got)

Chapter 1 (The Doctor)

It was a Wednesday. Wednesday was one of the clinic nights. How in the world did Hiro forget about that very fact? It flew right past his head. "Where's Baymax?" Aunt Cass questioned, and that was when it finally hit him and he felt guilt arising from his stomach. How did that fly right by him?

Every Wednesday night for the past four months, Baymax had work at the nearby clinic and Hiro would pick him up on the city bus after school was over. It was originally Cass' idea. Hiro agreed because it was what Tadashi would have wanted. He created Baymax in the first place so that he could help the sick and injured and a few boring and lonely Wednesday nights would suffice in exchange for what his brother wanted. Also, the robot looked the happiest whenever he could help those around him, not that he had the emotional expressions to match. Every time he would tell him his shift was over, Hiro always heard happiness in his tone of voice. It wasn't surprising; after all, it was what Baymax was programmed to do in the first place.

The teenaged prodigy sighed. He felt really bad about forgetting about that. That was when he realized the true extent of how tired he was. The night before, he was studying for his finals coming up the next week for more than a few hours. Once the clock went past 10:30, Baymax wasn't asking anymore and was demanding he should get some rest. Hiro had to refuse and test his patience levels. Of course his robot friend won within minutes of struggles, only because of his persistent programming. He had to lift Hiro up bridal style off of his computer desk and to his bed. When Hiro woke up the following morning, he was emotionally and physically exhausted. This morning, Baymax stated that it was because of his melatonin levels, his previous cold (that was dying off rather quickly) and his stress levels. Hiro never really could've thought that he would be so tired that he would completely forget that it was clinic night.

He dropped his backpack, and told his aunt his intentions before he took the next city bus to pick up Baymax from the clinic. His shift ended two hours ago and that was what made him feel guiltier about his forgetful thoughts. The city bus was really uncomfortable without Baymax and he honestly felt a bit unsafe. A few people actually noticed that he was all alone this time.

He opened the hospital doors and the front desk lady smiled. "Hello. Are you here for Baymax?" They have been doing this for quite a while, four months in fact. The lady and a majority of her coworkers actually understood his intentions and even recognized that he was a bit behind schedule. Hiro nodded slowly and uttered a small sorry for his tardiness, in which she understood. The clinic wasn't busy for a Wednesday night. In fact, they were going to close up shop in an hour or so. The front desk lady (maybe Hiro should actually take the time to learn her name) beamed before she ordered him to follow her to where Baymax worked.

"Hello, Hiro." Baymax's monotone voice called out. Again, he looked happy, despite his lack of emotional convexes. "Hey buddy." Hiro greeted. "Sorry I'm late, I kind of forgot."

"Your forgetfulness may be due to sleep deprivation. Your melatonin levels are low. I suggest you get a range of eight to ten hours of sleep tonight." Baymax instructed, similar to what he stated this morning. The nursing bot stated that his health (either mental or physical) should come before any school work. Hiro agreed half heartedly and the robot questioned if it was about time to go home.

Due to the not so flexible bus schedules, they would have to walk home. There was nothing to complain about, it wasn't really that long of a walk anyway. He put on his jacket and was about to walk out the door and quickly on the path home, until he was stopped by one of the doctors who worked in the same field as Baymax. "Excuse me," The doctor called. Hiro turned around. "Before you leave, I have something to ask," He felt nervous suddenly and before Hiro could even offer a response, the doctor interrupted him. "My patients love Baymax and he is very good at his job. I would love to pay you all of that this clinic has if you would allow him to stay and work here fulltime and overnight hours." The doctor finished his statement while Hiro's heart fell down to his toes. Wednesdays were already lonely enough as it is. Of course, this is what his brother would have wanted but he never wanted to let his robot friend go, he had grown rather attached to him. Instead of making a decision, Hiro merely grabbed Baymax's squishy arm out of security. Somewhere he mumbled that Baymax wasn't for sale.

"Oh, that's too bad. If you ever change your mind, the offer still stands," The doctor still smiled genuinely. Hiro was convinced that he wouldn't change his mind. No…He's not going to lose Baymax again. "Have a good night," the doctor bid his farewell and walked away. He opened the door, surprised when a gust of cold night air sent chills down his spine.

The city of San Fransokyo was alive, with cars driving down the highways and the lights in the towers illuminating the streets. Winter was already here, along with the upcoming holidays. Another night gust blew through the streets, a storm was brewing. "Your temperature levels are lowering." Baymax noticed. Hiro didn't say a thing. He was still caught up in the offer that the doctor gave him a few minutes before. Should he let Baymax go? It seemed like the right thing to do, the patients in that hospital needed all of the help that they could get. He suddenly felt selfish for saying no.

Sure, his nursing bot took care of him. In some situations he wouldn't leave him alone until he put a bandage on a minor scrape. Last week, he had a cold and Baymax took care of him almost obsessively, regularly giving him water, warmth, a bowl of chicken noodle soup every once in a while, and medicine. (And you would be rather surprised on how appetizing Baymax's chicken noodle soup is.) Baymax comforts him whenever he misses Tadashi, and helps overcome it by going on regular flights. However, Hiro wasn't sick anymore; he didn't have depression and wasn't tackling with loss like he did months ago. He felt if Baymax had more people to help, that he would be happier. He didn't care about money. After all, if he ever got desperate, he could go back to illegal bot fighting if he really needs to. This was about Baymax. Not about money.

"I advise that we go home quickly, your lowering temperature levels are not helping you recover from your cold. I am also detecting levels of distress, Hiro." Baymax's gentle voice called out, interrupting the silence. After a few minutes, Hiro finally felt it was the time to ask. "Would you want to work fulltime? Would you be happier that way?" His eyes looked sad but his words sounded hopeful.

"Is this the cause of your stress?" Baymax inferred, not answering his question.

"No. It's just…Tadashi would've wanted you to help people. You helped me but I'm not sick anymore, buddy." It had been months since Hiro said Tadashi's name aloud. It felt just like a sound or a noise to him.

"That is not true, Hiro. You are recovering from the common cold and are experiencing fatigue due to stress and lack of sleep. Your emotional status is fluctuating due to pubescent—"

"Yes, yes. I get that." Hiro interrupted him, growing a little frustrated, "But am I dying, Baymax?"

"No. Although your heath habits are not the greatest, your conditions are not life-threatening."

"Exactly! I'm not dying but the patients at the hospital are so sick that they are dying." He didn't quite understand why he was trying to persuade Baymax on working fulltime. "They need you, Baymax." Honestly, he didn't want him to leave.

Without his brother, life was difficult by default. He remembered his brother's funeral. The day after that, everything felt like a blur and everyday that passed, Hiro felt more and more incomplete. He slept most of the day, refused to go to school and even refused to eat, he just didn't have the motivation or the appetite to do so. The boy didn't even bother to get out of his room for three months. Once Baymax went back online, everything changed. He grew really attached to the nursebot and he couldn't believe that at first he thought he was a pain. During the first week after Baymax has been online, he actually persuaded him to eat regularly and got him outside. Slowly over time, the robot filled in that void that Tadashi left behind. Sure, he still missed Tadashi, especially now during the holidays. He regularly had nightmares about the fire, and a few panic attacks here and there. The wound was still there, but Baymax was always there to help and give him comfort whenever his night terrors return.

Hiro recalled the time where he lost him. How lonely and sad he was. He was right back to square one, until he noticed that the smart bot kept his chip. Those few months reviving him were the longest in a while but thanks to the blueprints on his computer during his scans, he was able to do so ever so easily. Did he really want to go back to those times without Baymax?

Why was he doing this? Why was he going let him go after all his hard work? Truth is, Hiro didn't even know the answer to that question. "Would you want me to stay at the clinic? There could be a chance that you would never see again." Baymax replied, getting Hiro's mind back into the real world.

"I asked you first. I don't want you to go but if you would be happier doing what you were programmed to do, then I don't mind." Hiro tried to explain, another cold gust of evening air went right through his jacket as he started to shiver. He let out a coughing fit, and he could practically feel Baymax worrying about him as he repeated for the tenth time that Hiro needs to go home as soon as possible and that his temperature was decreased. For a minute, Baymax was quiet and he didn't really know what to say to him. For the first time, Baymax couldn't understand how Hiro was feeling, he scanned him multiple times but the words he used didn't match his current emotional state. The nursebot dismissed the data but kept it in mind for later. Not sure what to say, he replied with, "I am a robot. I am incapable of making these decisions."

"You're more than a robot. You're my best friend." Hiro admitted. He didn't lie. Baymax felt a surge in his circuits that identified as an emotion, although didn't react to it in any way. After all, he wasn't programmed to be equipped with emotions; it was something he picked up on when he downloaded data to help others. "Hiro, you are my patient. If you are satisfied with your care then I will leave only if that is what you choose." Hiro coughed again and then let out a sneeze. "I will not leave you." Baymax concluded.

"Huh?"

"Your cold is only getting worse. I will not leave you until you are feeling better again." Baymax explained. Hiro laughed as he shivered lightly. "Okay, buddy. We'll worry about that later." He sniffled and noticed that they were home. Hiro opened the doors and said goodnight to his aunt before he retreated upstairs. Before he decided to study, he charged Baymax, just in case. He continued to shiver for quite a while as he put his nose in his college textbooks. Why did he have to forget clinic night today? He could have had an extra hour or two of daylight to study. Finals were arriving quite soon and Hiro has been out of sorts, he was already exhausted the second he started to study. He sniffled and forgot how quickly Baymax charged. The nursebot startled him once he leaned against his back with his heaters activated.

"Maybe you should rest."

"But I'm not tired," Hiro stated, as he read. He coughed a few times and groaned. From Baymax's scans, Hiro really was tired, reaching exhaustion. It worried him knowing that his patient wasn't taking care of himself, so he scooped him out of his chair. "Stop stop stop, Baymax I'm not done!" Hiro struggled a few times. He knew that he couldn't win this fight so he huffed in defeat. Baymax activated his heaters and the teenager yawned slowly. Baymax waited wordlessly and Hiro fell straight to sleep within minutes. That night was dreamless for him, no nightmares woke him up. It was a peaceful night. Baymax knew he wasn't programmed to bond with his patients, however, somewhere inside of him wanted to stay with Hiro and protect him until the boy's last breath. He didn't utter a word.