Character development is key. Fanfictions explore how Ace and Luffy grow under Garp's influence. Maybe Luffy becomes more disciplined in some stories, or Ace learns to be more open - hearted, all thanks to their interactions with Garp and each other.
One possible plot could be that Luffy gets into a really tough situation during his adventures, perhaps surrounded by powerful enemies on an unknown island. In desperation, he calls out to Garp for help. Garp, despite his tough exterior, races to his grandson's aid. Along the way, he might reminisce about Luffy's growth and how far he has come.
In addition to Luffy and Garp, other characters could also play important roles. For example, some of Luffy's crewmates like Zoro or Nami might be present when Luffy calls Garp. They could add their own perspectives and reactions. Also, there could be some marines around Garp when he receives the call, and their reactions to Garp's decision to go to Luffy could also be part of the story.
One popular ace luffy garp fanfiction is 'The Bonds of Family'. It delves deep into the complex relationships between Ace, Luffy, and Garp. It shows how their different personalities interact and how their family bond influences their actions.
I don't have enough context to determine exactly who 'garp' is. It could be a newly created character by the fanfic writer, or it might be a character from a relatively unknown story that is being incorporated into the 'ace fanfic'.
In fanfic, baby Luffy is often depicted as extremely curious. He's always eager to explore his surroundings, whether it's the small village on Dawn Island or the beach. His curiosity is so strong that it sometimes gets him into trouble, but he doesn't seem to mind.
It's possible that the baby's parents are from a rival pirate crew. In the 'luffy finds a baby fanfiction', this could lead to a lot of drama as Luffy has to decide whether to return the baby to its potentially dangerous family or keep it safe with his own crew. Or perhaps the baby's parents were victims of a powerful and evil force, and Luffy feels compelled to protect the baby from the same fate.