Things You'll Need
Instructions
Defeat the giant Twilight Bug at Lake Hylia.
Go to Hyrule Castle Town as a human. Go to the Southeast Alleyway and look for a door. Inside will be Agitha.
Give Agitha any Golden Bug you have collected. In return, she will give you the Adult Wallet.
Collect all 24 Golden Bugs.
Take them to Agitha and she will give you the Giant Wallet.