It's not appropriate at all. Fanfiction should be a form of creative expression that is positive and respects the source material and its fans. Writing about non - consensual and inappropriate scenarios like this can make other fans uncomfortable and can also give the entire fan community a bad reputation.
I'm not really into lemon fanfictions as they often contain inappropriate content. However, you can try searching on some fanfiction platforms like Archive of Our Own. Just keep in mind to abide by the platform's rules and guidelines.
One common theme is friendship. Often, the child forms an unexpected friendship with one or more of the animatronics. For example, they might bond over shared experiences or a sense of loneliness.
Foxy in these fanfictions is frequently portrayed with a sense of loyalty. He might be the type to stay by the Reader's side through various dangerous situations in the FNAF world. His broken - down appearance in some versions of the game also adds to the pathos in the fanfictions. Writers often play on his 'outcast' status among the other animatronics, which can make for some interesting relationship dynamics with the Reader.
One possible scenario could be that in the fanfic, Foxy runs away because he's scared of something in the pizzeria. Maybe he's afraid of the new security measures that are being put in place which he doesn't understand. As for the Foxy x Reader part, perhaps the reader is the only one who can understand Foxy's distress and tries to find him.
Well, in 'fnaf x male reader fanfiction', the theme of isolation is common. The male reader is often alone in the pizzeria or in the FNAF world, which adds to the sense of dread. Another theme is the struggle for power. Sometimes the male reader has to fight against the animatronics' control or the power they hold over the environment. Additionally, the theme of redemption can also be found in some stories. For example, the male reader might try to redeem the animatronics from their haunted state or find a way to make peace with the horrors of the FNAF world.
Survival is also a big theme. The male reader is typically in a situation where he has to survive the night against the animatronics' attacks. And sometimes, there's a theme of redemption. For example, if an animatronic has done bad things, the male reader might try to help it find redemption in some stories. This can add an interesting layer to the overall plot.
You could write a friendly adventure - based 'FNAF x reader' fanfiction. For example, the reader could be a new security guard at the pizzeria and they have to solve mysteries with the animatronics in a non - threatening and positive way.
Another theme could be the struggle of being in a relationship that is not considered 'normal' in the context of the FNAF world. There might be challenges like acceptance from other characters or dealing with the dangerous and spooky nature of the FNAF setting while being in a relationship. Often, there is also a theme of protecting each other. The male reader and the FNAF character might protect each other from the threats within the FNAF universe, which in turn strengthens their bond.
To write an interesting plot, think about the backstory of Foxy. Maybe the reader stumbles upon a secret about Foxy's creation that changes their relationship. You can also include other animatronics in the story to create more conflict. For instance, if the other animatronics are jealous of Foxy's connection with the reader. Also, don't forget to build up the tension. The reader could be constantly in danger, and Foxy is their only hope. This keeps the reader on the edge of their seat.