This is very rare, but it does happen in some cases due to the mishandling shipping carrier. As you know we carefully package each box. We use strong boxes, wrap each item in bubble wrap, and use packaging material inside the box also. We do this to make sure you don't receive a damaged item, but when your item is in transit, it's out of our control.
If you do receive a damaged package, please inspect it carefully and make sure the item is damaged and not just the shipping box. If the item is damaged, please take photos of the damaged box, item, and fill out a claims form at your local post office. Once you do that, please send us the photos and claims number. We will give that information to Japan Post and wait for an investigation. If Japan Post approves the claim, we will reimburse you for the insured amount.