Khane

Khane (가네 Kane) is the younger sister of a war hero who sealed herself within the Wall of Peaceful Coexistence. She's the only one who remembers her sister and her sacrifice as the other people of her town had their memories of her erased.

History
Long ago, she was talking to her sister and trying to convince her not to seal herself within the wall. She states that the army is trying to put pressure on her and that they're simply exhausted. Her sister tells her that she doesn't mind as long as it brings peace.