Formally known as Swedish Flag Day until 1983, the holiday commemorates the ascension of King Gustav Vasa to the Swedish throne on the 6th of June, 1523. This was following the Swedish War of Liberation (1521 - 1523) against Denmark, which also saw the dissolution of the Kalmar Union (a personal union of Demark, Norway, and Sweden where the Danes held the most power).
First observed in 1916 at the Stockholm Olympic Stadium, it didn't become a full-fledged holiday until decades later, before finally become an offiial public holiday in 2005.
One notable thing is the King of Sweden inviting and allowing the general public to tour parts of the Stockholm Palace for free on this day.
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As for the pic, I can't vouch for its accuracy. Perhaps our resident Swede can render a proper analysis.

What's more, I hear they're actually teaching *children* these things... in school!
Even more alarming, they're also being taught about... homonymy.

In Korone's case, the owner's most likely Okayu.

I'm sure many long for this, but the crushing reality that they're not anime girls invariably sets in.

It must be hard to be so inspiring on the fly.

Once again? How many times has this happened?

She's a great Servant.

Uh, there aren't any pipes there. I don't think there was a toilet to begin with.

[State-approved comment]

Must be how they got so chonky.

Society says they can't be together. But society can't stop the mlems.

No doubt before having a heated wrestling match, as friends are known to do.

But remember, "cancel culture" bad. >:(

"I'm a shooting star leaping through the sky like a tiger
Defying the laws of gravity
I'm a racing car passing by like Lady Godiva
I'm gonna go, go, go, there's no stopping me"

Or use SauceNao.

Duel Links... Could be interesting.

It's kind of amazing how one backwards, loud mouth demagogue can set human rights discourse back 20 years, if not more.
On the bright side, that also means some good ol' 2000's atheism.

No better time for yuri memes than June.
Does Pride Month also include pride at being an incurable yuri fiend?