There's a fanfiction called 'Nightmare's Bond with Fredbear'. In this story, it shows how their connection forms in the nightmare realm. It has some interesting character developments and explores their shared dark nature. The descriptions of the nightmare world are really vivid.
One common theme is the exploration of darkness. Since both characters have rather menacing aspects, fanfictions often delve into the darker sides of their existence and how they interact within that realm of darkness.
I also know 'Fredbear and Nightmare: A Forbidden Alliance'. This one explores the idea of an alliance between them which is quite unexpected. It really plays with the characters' personalities and the overall atmosphere of the FNAF universe.
A really unique plot might be that Springtrap and Nightmare are both pawns in a larger game. A mysterious entity is controlling their actions and they start to suspect it. As they try to break free from this control, they learn more about each other's true natures and form an unlikely alliance against the real enemy.
To develop Springtrap's personality, we could look at his past experiences in the Freddy Fazbear's Pizza place. His memories of the place, the people he knew, and the events that led to his current state could all influence how he behaves in the fanfiction. He might be bitter about his fate or still hold onto some remnants of his humanity. For Nightmare, his personality could be shaped by his relationship with the other Nightmare animatronics. If he is the leader, how does he lead? Is he a tyrant or a more benevolent figure? These aspects can be explored to develop his personality in the context of the Springtrap x Nightmare fanfiction.
The Fredbear back story involves a character from the Five Nights at Freddy's series. Fredbear was an early animatronic. He was part of a family - friendly restaurant concept that eventually led to a lot of mystery and horror elements in the game series. He was often associated with the bite of '87 incident which added to his dark lore.
Often, an original female character created by the author is paired with Springtrap. This gives the writer a lot of freedom to shape the relationship. Another possibility is a brave and curious male character who is intrigued by Springtrap and falls in love with him.
In fanfiction, Springtrap and Mangle often appear in some really interesting scenarios. Some fanfictions might focus on their spooky interactions within the dark and eerie setting of the FNAF world. They could be depicted as having a sort of rivalry, given their different natures in the original game lore.
Well, in fanfiction, Springtrap can be seen as a symbol of the horror that lurks within the Freddy Fazbear's franchise. His character is often explored in relation to themes like death, revenge, and the consequences of past sins. Writers might give him unique abilities, such as the ability to move silently or to manipulate the environment to his advantage. His backstory, which is full of mystery in the original game, is often expanded upon in fanfiction, which can add depth to his character.