Perhaps a fanfiction about their first time sharing a real, honest conversation. It could be after a near - death experience for both of them. They find themselves in a safe house, and for once, they drop their guards. Edward starts talking about his lonely childhood with his intelligence being his only friend, and Oswald shares his dreams of ruling Gotham. This heart - to - heart could be the turning point in their relationship.
Keep it in character. Oswald is likely to be hesitant yet eager. He might initiate it in a moment of boldness, like after a victory against a common enemy. Edward, on the other hand, could be initially surprised but then respond passionately as he realizes his feelings. Describe the physical sensations, like the softness of their lips meeting and the quickening of their breaths.
One idea could be their first fishing trip. The son learns how to bait the hook from his mom, they sit in the boat waiting patiently for a catch, and when they finally reel in a fish, they share a proud moment. Another could be their first time volunteering at a local shelter. They help feed the animals and clean the cages, and through this, they learn about compassion together.
One plot idea could be that Magnus and Alec go on a magical adventure together for the first time. They encounter a mysterious magical creature that is causing chaos in the Shadow World. As they work together to solve the problem, their relationship deepens. Another idea is that it's their first time attending a Downworlder - Shadowhunter event together. There they face some prejudice from both sides but their love for each other helps them overcome it. A third plot could be that they have their first real argument and then make up in a very romantic way, exploring more about their different personalities and how they can complement each other.
One idea could be an OC with the psychic power of seeing the last moments of a victim's life. This would add a new dimension to the CSI NY investigations as they could use this information to track down suspects. Another idea is an OC whose psychic power is to sense if a person is lying. This would be extremely useful during interrogations in the show.
One plot idea could be that Carmilla and Laura are exploring an old, haunted castle together for the first time. They hold hands as they walk through the dark corridors, and Laura starts to feel a strange connection to Carmilla that she can't explain. Another idea is that they're at a school dance and share their first dance, which leads to some sweet and awkward conversations as they get to know each other better on an emotional level. A third idea might be that they are in a library, and while reaching for the same book, their fingers touch for the first time, and from that moment, they start to have a series of adventures around the campus.
Perhaps it could be set during a special event like a ball at the academy. Rose is all dressed up and Dimitri can't take his eyes off her. They steal away to a quiet corner of the garden and share their first kiss and their first real conversation about their deep - seated feelings. This would be a more romantic and traditional approach to the 'first time' concept.
A plot idea could be that Warner and Juliet are from rival families or groups. Their first meeting is hostile, but then they discover they have more in common than they thought. This discovery leads to their first time interacting in a more positive way, like sharing a meal together and gradually falling for each other.
Well, perhaps they first time could be a part of a healing process for both of them. Jacob has his own traumas related to his shape - shifting and Bella has been through a lot in her relationship with Edward. They could find solace and a new beginning in each other, and this first time could symbolize that fresh start in their relationship.
One idea could be a scenario where they have their first time during a snowed - in situation at the inn. They finally admit their deep feelings for each other and the cozy, isolated setting makes it a very romantic moment.
A third plot idea could be a 'what if' scenario. What if they had their first time under the influence of a meta - human power that made them more open and vulnerable? This could lead to some interesting character exploration as they deal with the consequences of this unexpected event. They would have to navigate their feelings and the changes in their relationship while also dealing with the potential danger of the meta - human's power still being out there.