[Armin nods. Of course, Eren would give something to Mikasa. If no one else, Eren would give something to Mikasa. He asked Armin not to tell her what he said - that he never wanted her to move on, that he wanted her to think of him forever. Armin had just gotten done punching him square in the jaw for how he'd treated her; after that, he felt sad for him. Eren was a simple enough person, in certain ways...

[Maybe some small part of him feared that Eren wouldn't have the courage to give Mikasa what little he still could. He's glad to hear that that isn't true, though his smile is sad, subdued.]

Eren showed me all of the things we always dreamt of seeing. Not just the sea, but the fiery mountains, the fields of ice, even lights in the sky. It was beautiful...

[Armin indicates the shell with a nod, starting to reach for it again, then remembering. He pulls his hands back.]

Eren noticed this shell for the first time - the way it looks now. He couldn't see what was in front of him at the time...[Not until it was far too late...]

It's not much of a story, really. You get it. More than anyone, I think...

That shell...is Eren's sin, but...it's mine too. [For what he's done, the lives he's taken. Mikasa will understand. That's why he tells her. That, and a trust that runs so deep it rivals only that that they felt with Eren.

[Come to think of it, that trust was broken too; maybe Armin truly trusts Mikasa more than anyone.]

I don't mind it. I accept it, I just...[He wishes that Eren and he were still together to shoulder that sin.

[He shrugs, unsure of how to say it.] Well, I accept it.