Chapter Text
This one is a bit different than my headcanons in other series in where Tenma and Johan weren't immediately conditioned to live together not long after Johan's escape from the hospital.
Tenma returned to work with Doctors Without Borders in conflict areas. They were always short-staffed there. And 1-2 years later came a new and dashing rookie nurse, Johan, to be put in the same team as Dr. Tenma.
Of course, his practice license was forged or skipped some degrees and prerequisites, just like when he attended University in Munich. Somehow it passed the legal evaluation, most likely due to his connections and a bit of bribery at play, and because Johan was naturally a genius, he did go to training, and was adept at it to some degree. At least enough not to harm a patient.
Tenma's bosses and coworkers, the doctors, the nurses, couldn't be happier to have a new, handsome, young, and capable recruit. Every one in the team was exuberant, except for Tenma who was perplexed beyond belief when they gathered to greet the new highly anticipated recruit, his boss came to call him inside the meeting room, and imagine his surprise when the one who walked behind his boss, entering the room in all his glory with his sweet serene smile, beautiful face, and the confidence as if he owned the floor, was none other than Johan Liebert, a guy who he could never forget for the rest of his life, even if he wanted to. And even till now still haunted him in his dreams. Anxiety kicked in like a trained reflex in Tenma. The only thing his brain could catch up with, and his heart felt relieved amidst all the unexpected, shocking elements, was the fact that Johan seemed to recover well, without any visible disabilities or sequelae due to his last gunshot.
And because Johan would be working in the team that Tenma led, as a new addition, he'd be trained directly by Tenma and the head nurse (who was about to resign in a month) to accustom himself to Tenma's workflow and instructions in the OT.
After their introduction, and everybody who greeted him left, Tenma didn't waste any more time. He grabbed the young man's wrist, led them to a secluded corner away from everyone's eyes, and demanded an explanation.
The more Johan opened his mouth and answered, the more frustrated Tenma became. Like it or not, the official papers submitted to their headquarters showed that Johan was recruited through legal means and evaluations.
Tenma threatened Johan that if he ever so much as thought of harming any of his patients, he'd make sure to deport him back to Germany. To which Johan only smiled calmly and said, "Beneficence. My dear Doctor. I am here for you. Not for your patients. But rest assured, nonmaleficence. I can guarantee you that. There's no advantage for me to harm anyone here."
Tenma's superior, the boss at their headquarters, who happened to pass by and saw the commotion between them, asked if there was anything wrong.
Johan beat him to it and calmly answered on his behalf that he and Tenma were old acquaintances and that Tenma had known him since he was little and was already like a family friend of his parents.
Tenma's boss was suddenly delighted even more and said in that case, it'd be better for Johan to stay at Tenma's place assigned by the headquarters during the training so it would help him assimilate quicker as Tenma's assistant and to their workplace environment and work ethics. Tenma wanted to refuse vehemently, but the boss asked if Tenma would rather let his young relative to be sharing small dorms with the other new recruits rather than let him live with him?
"Don't you feel sorry for the young man, doctor?" he asked, bewildered by Tenma's response.
Tenma felt like tearing his hair, but his boss had decided, clearly being smitten by Johan's charms for whatever reason. Johan, on the other hand, just kept on smiling amicably.
And thus began Johan working as a rookie nurse, training as Dr Tenma's main assistant on the team, who, at the end of the da,y after a long day of work and surgeries, resided together to their humble abode.
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The settings are that they travel together with DWB as a team, hopping countries. For some reason, no matter what country they are stationed in next, Johan is always in the same team as Tenma.
After some time, because they work well and seamlessly together, the HQ just assigns them as a set team. And Johan rapidly climbs the professional ladder and becomes the head nurse.
The countries they travel to are any conflict and poorly developed areas.