It could be that Sherlock's disregard for danger during their investigations made John feel like he was too reckless. John, being more down - to - earth, might see Sherlock's fearless approach as abnormal or 'freakish'. For example, when Sherlock jumps into dangerous situations without thinking about the consequences, it might annoy John to the point where he uses such a harsh term.
Maybe John was frustrated at Sherlock's eccentric behavior. Sherlock often acts in ways that are outside of normal social norms, like his extreme focus on cases and disregard for basic social niceties. This could have led John to lash out and call him a 'freak' in a moment of exasperation.
Perhaps John was having a bad day and Sherlock's usual quirks, which he normally tolerates, became too much for him. Sherlock has many habits like his strange experiments in the flat or his lack of personal space awareness. On this particular day, John's patience ran out and he snapped, calling Sherlock a freak.
He might be initially shocked. Sherlock is used to John being more understanding, so this outburst could catch him off - guard. But then he could go into his logical mode and start analyzing why John would say such a thing.
Often, they explore different relationship dynamics. With a female John, the emotional exchanges can be more nuanced. For example, the way she might communicate her thoughts and feelings to Sherlock could be different from a male John.
There's also 'John and Sherlock: The New Case'. This fanfic delves deep into the psychological aspects of both characters as they face a particularly complex case. It's really interesting how the writer explores their thought processes and how they interact with each other during the investigation.
One common theme is friendship. Their relationship starts as a rather odd friendship between a brilliant detective and an ex - military doctor. Many fanfics explore how they grow to rely on each other more and more.
The fanfic could also focus on the challenges they face in society as a non - traditional family. John and Sherlock might face discrimination or skepticism from others when they try to adopt Harry. However, they persevere because of their love for Harry and each other. This could show how their strong bond helps them overcome external difficulties and build a loving home for Harry.
If Sherlock was John's kid, it could change the nature of their relationship. There might be more protectiveness from John and a sense of inheritance in Sherlock's detective skills.
If Sherlock was John's kid, it would likely bring a unique emotional depth to the story. It might force them to confront personal issues while still trying to crack cases. It could be a fresh and exciting take on the usual detective duo.
One popular one is 'The Great Game of Love' which beautifully explores Sherlock's internal struggle with his feelings for John. It has great character development.
One common theme is the exploration of their unspoken feelings. In many fanfics, Sherlock and John have deep emotions for each other that they struggle to express. Another theme is the idea of loyalty and how it plays out in their relationship. They are extremely loyal to each other, and this often gets tested in different scenarios in the fanfics.
Fanfiction.net is also a good place. There are many John Sherlock fanfics there. However, the quality may vary, so you might need to read the reviews or summaries before diving in. Some authors on this site have been writing John Sherlock fanfic for years and have a loyal following.