Get out of my OO!

Origin

The line comes from a joint stream of Project Zomboid by the Korean streamer group Sanakhoe. After dying and respawning, the member Samsik was building a makeshift base he called "Utopia" on his own, and when fellow streamer Han Dong-suk came looking for him, Samsik shouted over the radio: "Get out of my kingdom!"

The joke turns on the mismatch between scale and emotion. In a zombie apocalypse he has thrown together a shack-grade outpost, calls it a kingdom, and erupts with possessiveness over it. Worse, the person he is expelling is not an intruder but a teammate who came out of concern. The moment attachment to something you built curdles into territorial pettiness is captured intact.

Spread

What made it a meme is how easy the slot is to swap. Anything can go where "kingdom" was, and the shabbier the referent, the funnier it gets. In practice, then, the blank is filled far more often with "my house," a game title, a server name or a group chat than with anything grand.

It spread from the streamers' viewers into gaming communities generally. Because the meaning — exaggerated fury at having your territory invaded — carries without the source, people who never watched the stream adopted the same construction.

Usage

When someone enters your space — half-joking territorialism
When someone joins your game, server or channel — pretending to expel rather than welcome
Overstating a trivial possession — the pettier the better
When a teammate interferes — as a refusal of help

Variants and derivatives

The base form is "Get out of my X," and the original "Get out of my kingdom" remains in use as well. It extends past places to accounts, streams and chatrooms — anything you can claim as yours fits the blank.

It is often quoted alongside other lines from the same broadcast, since that Zomboid session is remembered as an episode that generated several memes at once.