In addition to his family and friends, the medical ninja in the village would be involved. They would be the ones to accurately diagnose Boruto's condition. Shizune, for example, could come and check on him, using her vast medical knowledge. And the other young medical ninjas might learn from this case, as Boruto's illness could be something new or unusual, so they would be eager to assist and gain experience while taking care of him.
It could be a rogue ninja who has a personal vendetta against Boruto's family. This ninja might have caused harm to Boruto's father Naruto in the past, and now Boruto is determined to make him pay.
In the 'Boruto Gets Sick' fanfiction, Boruto might experience various symptoms like a high fever, weakness, and coughing. His friends and family would likely be worried about him. They would probably take care of him, bring him medicine and try to make him comfortable.
Well, maybe Boruto's family or friends are hurt by a powerful enemy. So he decides to train hard and seek revenge. He might travel to different places to learn new jutsu and gather allies along the way.
Well, in 'tos lloyd gets controlled' fanfiction, themes can vary widely. One might be the exploration of Lloyd's identity while being controlled. How much of his true self remains? Another theme could be the power dynamics between the controlling entity and Lloyd. Is it a battle of wills? And there could be a theme of redemption if Lloyd manages to break free from the control. It all depends on the writer's take on the concept, but these are some of the common themes that could be explored.
The Akatsuki could be likely antagonists. They are always interested in powerful ninja like Naruto. They might use some forbidden jutsu to control Naruto to further their goals of collecting the tailed beasts. Another possibility is Orochimaru. He is always looking for ways to gain power and Naruto's power would be very appealing. He could try to control Naruto to use him in his experiments or to fight his enemies for him.
Well, in some fanfictions, Naruto gets controlled by a mind - altering device created by a rogue scientist from another village. This device makes Naruto do things that are out of character, like stealing important ninja scrolls. His friends initially suspect he has turned bad, but then they discover the truth and have to race against time to remove the device. Also, there could be a plot where Naruto is controlled by a powerful genjutsu cast by a long - lost relative who has a vendetta against the village and wants to use Naruto as a weapon to get revenge.
One likely antagonist could be a powerful new villain who has the ability to mind - control. This villain might target Deku specifically because of his potential as a hero. Another could be an old enemy of the hero society who sees Deku as a key to their revenge.
Maybe in the fanfiction, Boruto is abused by a powerful and evil villain who wants to get back at Naruto by hurting his son. The villain could use dark jutsu to physically and mentally torture Boruto.
There shouldn't be any such fanfiction. Boruto and Himawari are siblings in the Naruto universe, and creating a story about them in such a way goes against the basic values of family and propriety. It would also be unacceptable to a large number of fans who respect the original work.