One possible plot development could be that it's part of a game or a light - hearted situation. Maybe they are playing a role - playing game where this is part of the scenario. For example, they could be reenacting a scene from a movie or a story they both love.
Well, it could be a moment of intense emotion. Maybe Edward is angry or frustrated and his slamming into Bella is a moment of uncontrolled passion. It might lead to a big argument between them and then a subsequent making - up as they realize their feelings for each other are too strong to be torn apart by such a moment.
There could also be an external threat that forces them to put aside their differences. For example, a new vampire or a group of enemies might attack their community. In this situation, Edward, Bella, and Jasper have to work together. During this time, Edward might realize that his jealousy is unfounded, and they all form a stronger bond as a result.
In some fanfictions, they could face new threats from other supernatural beings. Maybe a new coven arrives in town, and they have to protect their family and the town. This would put their relationship to the test as they deal with the danger together.
One possible plot development could be Bella trying to find a way to escape the forced marriage. Maybe she discovers some hidden secrets about Edward or the circumstances that led to the forced union, which gives her leverage to break free.
I'm not sure of specific 'Edward ties Bella up' fanfictions off the top of my head. But you could also try FanFiction.net. Some authors might explore this concept in their stories. You may need to do some digging by looking through different categories related to the 'Twilight' series. Keep in mind that the quality and content can vary widely among different fanfictions.
King Edward might become more protective and less focused on his kingly duties at first. As the story progresses, he could learn to balance his love for Bella and the baby with his responsibilities. Bella could become more confident in her role as a future mother and a queen - like figure in the kingdom.
Another direction could be that they focus on building a normal life within the vampire world. They might start a school for other vampires or hybrids, teaching them how to co - exist with humans. Edward could use his knowledge of music and literature, and Bella could share her experiences of being human - turned - vampire.
Well, it could start with Jasper's reasons for turning Bella. Maybe he sees a potential in her that no one else does. After the transformation, Bella might go through a phase of self - discovery. She could be exploring the new world of vampires, learning about their history and culture. And there would be the inevitable love triangle or quadrangle situation. With her new vampire allure, she might attract other vampires, causing some jealousy or competition among them, especially if Edward is still in the picture.
One possible plot development could be that the Cullens launch a rescue mission. They might gather other vampire clans to help them, as the Volturi are very powerful. Another could be that Bella discovers some long - hidden secrets about the Volturi while in captivity, which changes her view of the vampire world completely.
One possible plot development could be that they face challenges in their relationship due to the unexpected pregnancy. Maybe there are family or social pressures.