Here are some title ideas. 'Jean & Marco: A 'Attack on Titan' Fanfic'. This is simple and straight to the point. Then there's 'The Jean - Marco Dynamic in 'Attack on Titan' Fanfic', which emphasizes their relationship. Also, 'Jean and Marco's Journey in 'Attack on Titan' Fanfic' could work well as it gives a sense of an adventure or story that unfolds between them.
In the 'Attack on Titan' Marco x Jean fanfiction, their relationship is often complex. They are comrades in the harsh world within the story. Jean initially may seem a bit self - centered, but Marco has a positive influence on him. Their bond is one of mutual growth, as they face the terrors of Titans together and also deal with the politics and rivalries within the military.
In the Attack on Titan manga, Jean remains alive. The story doesn't have his character meeting a fatal end. He continues to play a significant role and face various challenges along the way.