I don't think it's common to find a new one. This kind of pornographic comic related to a specific character is not usually widely available or promoted.
The story behind The Iron Giant involves a lonely boy finding a powerful and gentle robot. They face opposition from society, but their friendship prevails. It's a heartwarming and thought-provoking narrative about the power of kindness and the importance of seeing beyond appearances.
These stories can teach kids about friendship. Just like how the Iron Giant made friends in the stories, kids learn the value of accepting others. Also, the Iron Giant often showed kindness which is a great moral for kids.
One idea could be that Annie and Hogarth embark on an adventure to find a missing part of the Iron Giant, with Lemon as their guide. They could face various challenges along the way and form a stronger bond as friends.
In a fanfiction, Annie, Hogarth and Lemon could be in danger, and the Iron Giant comes to their rescue. After that, they decide to team up to prevent the same danger from happening again. They start training together, with the Iron Giant teaching them about his world, and Annie, Hogarth and Lemon teaching the Iron Giant about human values.
One storyline could be that they go on a journey to discover the origin of the Iron Giant. Annie and Hogarth team up with the Iron Giant, using their wits and the Giant's strength to overcome various obstacles and find out where the Giant came from.
One interesting story could be about the Iron Giant's first encounter with a small village. He was initially feared but then the villagers realized he was gentle. The Iron Giant might have helped them with some heavy lifting or protecting them from a small threat.
I'm not sure if there are specific fanfictions that involve all three without inappropriate content. However, you could start by looking at well - known fanfiction platforms like Archive of Our Own. Search for stories tagged with 'Iron Giant', 'Annie' and 'Hogarth' and read the summaries carefully to ensure they are appropriate.