I don't know why, but while I'm reading fanfiction and other things I notice that people sometimes quote how no one wants Eren to die because he's "the key to humanity". I've always thought he was immortal so that confused me.
Because of Eren's Titan skills, he heals fast, which seems kind of immortal.
Does Eren have a weak spot that will kill him?
Also note that Levi said in an episode that there is no way for Eren to die (at least as of that point, given that no one has found a way to do so), but there is a way to permanently injure him. So does that make him immortal? And why do people say he's not immortal like he will die or something?