One common theme is growth. Both characters are often shown to grow as individuals and in their relationship with each other. For example, Mori Jin might learn more about patience from Mira, and Mira could learn about taking risks from Mori Jin.
One idea could be to cross Mori Jin with a character from a different anime like Naruto. Mori Jin could end up in the Naruto world and have to deal with different jutsus and the ninja way. He might even teach some of the ninjas his own martial arts skills.
Light Yagami from Death Note. It would be a contrast in characters. Mori Jin could find himself in the world of the Death Note and try to stop Light's plans, or they could form an unlikely alliance where Mori Jin tries to change Light's view on justice while also dealing with the power of the Death Note.
One great Mori Jin x Mira fanfic is 'The Adventure Together'. It really delves into their relationship and how they support each other during different challenges. The story has some really interesting plot twists and great character development for both of them.
Takashi Mori is likely an author who writes science fiction. However, without more context, it's difficult to provide detailed information about his works. There could be many relatively unknown authors in the vast world of science fiction.
Mori Senpai would likely become more openly affectionate. In the series, he was often reserved, but as Haruhi's husband, he would show his love more freely. Haruhi, on the other hand, would probably become more aware of Mori's needs. For example, she might notice when he's tired or stressed and take steps to comfort him.
I'm not sure specifically which works Takashi Mori has written as there isn't much information provided. But he might have written short stories or novels related to time travel, as it is a common theme in science fiction.
One common theme is friendship development. Since they are from different personalities, exploring how they become closer friends is a popular topic. For example, Mori's quiet nature and Haruhi's more outspoken self learn to understand and complement each other.
Memento mori is a Latin phrase that means'remember that you will die'. A memento mori short story could be a short fictional narrative that somehow deals with themes related to mortality, the brevity of life, or the inescapable fact of death. It might feature characters coming to terms with their own mortality, or it could be a more symbolic exploration of death and how it affects the living.
Maybe the OC is a foreign exchange student who is lost on her first day at OHSHC. Mori comes across her and decides to help. He shows her around the school, and the OC is fascinated by Mori's calm and stoic nature. She starts to draw him in her sketchbook secretly, and when Mori finds out, he's flattered. This leads to a series of interactions where they get to know each other better and eventually fall in love.