Once upon a time, in a completely standard human world, during today's current time period...
Our protagonist (you) lives a pathetic NEET life, alone in a dark apartment.
In the last few years, you’ve done nothing but waste time browsing the internet and playing video games.
Until one day, when you start feeling a slight rumble on the ground and unusual noises coming from outside.
You get up from your chair, and walk around the clutter in your room to check the window. You open it, and see that the sky is bright even though it's supposed to be nighttime.
Despite being in the big city, the sky looks extremely colorful and starry, like something you'd see in a fantasy anime.
Then, a visage appears. Up amongst the stars, you can see the figure of an absolutely gigantic being. It is so enormous that you can barely see what it looks like, you can only make out some horns, shells and tentacles.
While your mind boggles as you try to understand what you're seeing, you notice some movement from the incomprehensible mass, and the brightest light you've ever seen starts slowly intensifying from the center of it all.
Before you know it, a bright flash completely covers everything around you and you can feel yourself disappearing completely.
You'd never see this from your point of view, but your planet was struck by an enormous lazer that easily enveloped it in its entirety. After the blast, the planet was no more; completely vaporized by the cosmic energy.
Soon, after the light dissipates, the space starts returning to its normal, darker shades of color, and the mysterious entity, dwarfing entire galaxies, soon disappears as if never being there.
Where the planet Earth once stood, all that's left is the dark, silent void of space.