The groping...

Why is this a problem?

Well first it's freaking weird but mostly it represents Korea claiming the Dokdo island from Japan.

Which is WRONG!

The Dokdo island is Korean territory NOT Japanese.

It should have been the other way around.

It should have been Japan trying to claim the Dokdo island, not Korea.

I believe Hidekaz Himaruya did this because he is Japanese so he probably believes the island should be rightfully Japan's.

This bit of information is a problem because it's spreading misinformation to people who read the manga. Imagine the false information spreading to a wider audience if this was in the anime.

Here is a small history lesson.

You can see the TL;DR at the bottom but I suggest that you please, please, PLEASE read all of this :)

Japan colonized Korea in 1910. They annexed everything. Islands and the mainland, this includes Dokdo. When Japan lost WWII in 1945 Japan had to relinquish all countries and islands that Japan has invaded. That includes Korea and Dokdo.

So what's the problem?

This is where the problem occurs

According to San Francisco Peace Treaty of 1951 Article 2, it states

"(a) Japan recognizing the independence of Korea, renounces all right, title and claim to Korea, including the isles of Quelpart, Port Hamilton, and Dagelet."

Japan noticed that it never mentioned Dokdo and that it wasn't in the article. So there was no reason to return it back to Korea. Therefore, it's still Japanese territory.

However, Dokdo is part of Dagelet. Which is stated in the article.

What's the big deal about this island?

Dokdo is right in the EEZ. Which means Exclusive economic zone. Whoever owns the island has special rights to the resources and fishing and whatever important economic stuff for a country.

Japan wants to widen its oceans. They want the resources from Dokdo even though it's rightfully Korea's.

Japan did go as far to create this odd concrete thing and claim it as 'a sovereign island' so they can expand their EEZ

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TL;DR

Japan annexed Korea and all its islands. 1910-1945

Japan lost WWII in 1945 and gave everything back to Korea except Dokdo because it didn't specifically say Dokdo in the Peace Treaty Article. But Dokdo is part of Dagelet which was said in the article.

Dokdo is important because it's in the exclusive economic zone.

Dokdo will and always be Korea's.