Communication is key. They can start by sharing their fears and hopes. For instance, Gregory can talk about his loneliness before coming to this place, and Vanessa can share her own struggles with her job. This mutual understanding will bring them closer.
The relationship can start with suspicion. Gregory is a strange kid in the pizzeria and Vanessa is an employee. But as they face danger together, like running from the animatronics, they start to trust each other more. For example, Gregory might save Vanessa from a sudden attack by one of the animatronics, and that could be a turning point.
One common theme is friendship. Since they are characters in the same universe, many fanfics explore how they become friends and support each other. For example, in some stories, Gregory might be in a difficult situation and Vanessa comes to his aid, and from there a strong friendship develops.
One common theme is trust. Since they are often in a dangerous and strange situation in the FNAF world, they have to learn to trust each other. For example, in many fanfictions, Gregory has to trust Vanessa's knowledge of the place to escape safely.
Some specific fandom - dedicated forums might also have Gregory x Vanessa fanfiction. These forums are often a great place to find more niche or unique stories that might not be as easily found on the larger fanfiction platforms. You can engage with other fans in these forums and ask for recommendations as well.
One great Gregory x Vanessa fanfiction could be one where they team up to solve a mystery in the game's setting. It might have them exploring hidden areas and relying on each other's unique skills.
A frequent theme is trust. Given the circumstances in the FNAF world, Gregory and Vanessa have to learn to trust one another. There's also the theme of redemption in some fanfictions. Vanessa may have a past she's not proud of, and through her relationship with Gregory, she might find a way to redeem herself. And of course, the overarching theme of facing fear is always there, as they are constantly confronted with the terrifying animatronics.
Well, you can try searching on fanfiction websites like Archive of Our Own. There are often many fanfics about different pairings, and you might find some great 'vanessa x gregory' ones there. Just use the search function and look for tags related to them.
It could be the malfunctioning animatronics. They are always a threat in the FNAF universe and could be constantly trying to harm Gregory while Vanessa tries to fend them off.
One idea could be that Vanessa and Gregory are on a mission to uncover the secrets of the old parts of the building they're in. They face various challenges together and their bond grows as they rely on each other's skills. For example, Gregory's quick thinking and Vanessa's knowledge of the place help them avoid the security mechanisms.