A more dramatic plot could be that the amnesia heroine is in danger from an unknown source. Toma has to protect her while also trying to help her remember who she is. As they face the threats together, she slowly falls in love with him, not knowing if she had any prior feelings before her amnesia.
One plot idea could be that the amnesia heroine starts to remember bits and pieces of her past as she spends time with Toma. Their relationship could be a mix of confusion and growing affection. For example, she might remember a special place they used to go to, and as they revisit it, their bond deepens.
Another idea is that Toma tries to help the amnesia heroine regain her memory by showing her things from her old life. But as he does this, she starts to uncover some secrets that Toma has been keeping from her. This could lead to a conflict that they have to work through to stay together.
To develop the amnesia heroine further, you can have her gradually gain some independence despite her memory loss. Maybe she starts to make decisions based on her new experiences. For Toma, show his own insecurities. He might be worried that she'll remember something that will change their relationship.
One common theme is friendship - turned - love. Often, the heroine and Toma start as friends and gradually develop romantic feelings for each other. Another theme is self - discovery. As the heroine gets closer to Toma, she also discovers more about herself. For example, she might find new strengths or weaknesses. Growth is also a theme. Both characters usually grow and change as a result of their relationship.
One popular 'heroine x toma fanfiction' story is 'A Chance Encounter'. In this story, the heroine meets Toma in a very unexpected situation, like in a small, old - fashioned bookstore. Their interaction starts off a bit rocky but then gradually develops into a deep connection. Another one could be 'Under the Starry Sky with Toma', where the heroine and Toma go on a camping trip together and share many heartfelt conversations under the night sky. And 'Toma's Hidden Smile' is also great. It focuses on how the heroine manages to bring out a side of Toma that he usually keeps hidden from others.
Another approach is to write a fanfic where Shin and the heroine are in a different time period. For example, a historical setting. This would change their dynamic and offer new storylines to explore.
A really interesting plot could be if the main character in the fanfiction actually has a connection to the ones who created the dark world. For example, he could be a descendant of an ancient cult member and his amnesia is somehow related to suppressing this dark family history. This could add a whole new layer of mystery and horror to the story.
A plot idea could be that the Muggle has a natural ability to resist magic due to some genetic quirk, which is related to his amnesia. Ginny, being interested in the study of magic and Muggles, tries to figure out how this is possible with Harry's help. They start to experiment with different spells and potions to not only restore his memory but also understand this unique ability of his, which could lead to some interesting discoveries about the relationship between magic and non - magic folk.
A plot idea could be that the sister has amnesia due to a vampire - related incident. Maybe she was bitten by a new type of vampire that causes memory loss. The other characters then have to find a cure while also protecting her from other threats in the vampire world.
One idea could be that Edward wakes up with amnesia and forgets his vampire nature. He starts living as a normal human, going to school and making new friends. This would lead to a lot of comical and also heart - wrenching moments as he slowly discovers his true self again.
One plot idea could be that Hiccup forgets all about his dragon - training skills and his relationship with Toothless. So, he has to start from scratch, relearning how to communicate with Toothless. This would create a lot of humorous and touching moments as Toothless tries to remind Hiccup of their bond.
One idea could be that Peter forgets his identity as Spider - Man. He starts to notice his strange abilities but has no idea where they come from. So he embarks on a journey to figure it out, all while his friends and family are trying to figure out what's wrong with him.