One idea could be creating an OC who is a long - lost relative of the Griffin family. Maybe a distant cousin from another country who comes to Quahog with a whole new set of values and traditions that clash and mesh with the Griffins' way of life. This could lead to some really hilarious and heartwarming situations as the family tries to adapt to this new addition.
Another interesting concept is an OC that is an alien. In the wacky world of Family Guy, an alien OC could interact with the characters in unique ways. They could have strange powers or habits that the Griffins and their friends find both fascinating and confusing. For example, the alien OC might think that Peter's love for beer is a strange religious ritual.
You could also make an OC who is a time - traveler. This OC could pop in and out of different time periods in Quahog's history. They might accidentally change some small events that have big consequences for the Griffin family and the town. It would be fun to see how the characters react to these unexpected changes in their timelines.
One idea could be a crossover with 'The Simpsons'. Imagine Peter Griffin and Homer Simpson getting into a wacky competition, like a donut - eating contest that somehow gets out of control. Another could be a crossover with 'South Park'. Maybe the kids from South Park visit Quahog and chaos ensues as the different humor styles clash. A third idea might be a crossover with a superhero universe. Picture Stewie teaming up with Spider - Man to save the day in a very 'Family Guy' - style adventure.
Another plot could be that the OC is a time - traveler who accidentally lands in Quahog. The female characters find his stories of different times and places fascinating. They start to form a harem - like group around him as they want to hear more about his adventures. Peter might initially be jealous but then end up getting involved in the OC's misadventures too.
Well, you could write a fanfiction where Meg finally finds true friends who appreciate her for who she is. Maybe a story where Lois discovers a hidden talent and pursues it, causing chaos in the family. Also, a tale about Quagmire having a serious relationship and how it affects his womanizing ways could be interesting.
One idea could be a story where Lois and Chris go on a wacky adventure together in a parallel universe. Maybe they discover a hidden talent in each other during this adventure.
One idea could be that Dora gets lost in Quahog and has to ask the Griffin family for help. Stewie could be really intrigued by her map and backpack and try to steal them for his own adventures. Another could be that Dora teams up with Brian to solve a mystery in town, like who's been stealing all the cheese from the local deli. Maybe they use Dora's language skills and Brian's detective skills.
One idea could be a crossover where Naruto characters end up in Quahog. Maybe Naruto and Peter Griffin become friends and Naruto tries to teach him some ninja moves. Another could be Stewie somehow getting his hands on Naruto's ninja tools and causing chaos in both their worlds.
Another concept could be a family guy character, like Peter, becoming a ninja in the Naruto world. He would struggle with the strict ninja training because of his lazy and gluttonous nature. But through his interactions with Naruto and the other ninjas, he could learn some valuable lessons about discipline and friendship. For example, he might start off as a joke but gradually earn the respect of the Konoha villagers.
An interesting plot could be an OC who is a noblewoman forced into an arranged marriage with Guy of Gisborne. At first, they clash due to their different personalities and loyalties. However, as they face common enemies and challenges together, they begin to develop feelings for each other. Or an OC who is a thief that Guy catches, but instead of punishing the thief right away, he uses the OC to gather information about other criminals in the area.
One idea could be a story where Brian and Stewie go on an adventure in outer space. They could encounter strange alien species and have to use their wits to get back home.
One idea could be that Stewie's pregnancy is a result of some wacky science experiment gone wrong in Quahog. Maybe he accidentally drank a potion that made him pregnant. Another could be a time - travel related fanfiction where Stewie travels to a future where male pregnancy is common and he somehow gets pregnant there.