Another difference lies in the overall mood. Canon AOT has a rather dark, gritty, and often hopeless mood due to the constant threat of Titans. However, a friendly Titan fanfic would likely have a more positive, hopeful mood. It might explore themes of redemption for the Titans, or how their existence could be beneficial to the world of AOT. This is a complete departure from the doom - and - gloom feeling that often pervades the official AOT story.