After learning Nen and becoming a true Hunter, Gon returns to Whale Island with Killua. When he arrives, Mito has a box for him. She was told by Ging to give this box to Gon once he became a Hunter. However, it appears that the box cannot be opened.
hunter-x-hunter-ep-37-2Hunter x Hunter Season 1 Episode 37
Hunter x Hunter Season 1 Episode 37
Ging x And x Gon!
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