It's blue outside.
Are you a visual person? I'm more of a lexical one. My field is with words; nevertheless, if a thousand words can paint a picture, let's try to do so with less.
Out of a half-open window, not ten minutes ago, I heard the soft blowing of the wind in the blue world outside and the single bark of a dog. Imagine, then, the dog. Where is he/she? Is his/her owner with him/her or not? What's the owner doing? Why did the dog bark? Maybe they are being walked. Can you visualise that? Okay, hold it in your head for a while.
Now can you imagine a single room inside a flat relatively near where the dog is. It sounds cols outside with the blowing of the wind, and looks cold as it's... well... blue. But imagine a room - a warm room. In fact, it's deliberately been made warm. There's a radiator and it's on. There are several convection heaters, too. The room is full of warm colours - all reds and yellows and oranges and browns. From the curtain drawn over the single window (blocking out the blue world) to the bedspread. Got that?
Okay, it's a small room. There's a large double bed in the middle of the room. On top of the bed, a young couple is having sex. It's sweaty. It's passionate. It's intense. He is on top; she is on her back, one hand pressed against the small of his back, pushing him down, further into her. I'm not getting any music. Maybe the occasional siren of an emergency vehicle outside (that's what I can hear right now), a car rumbling past or a dog (the same one?) barking. But there are relatively few other sounds... just the heavy breathing, gasps for air and the very realistic "uh..." noise you make during sex.
Not the screams you get in porn.
Can you visualise that? Yes, you probably can. I've given you a description - your head just fills in the blanks. But what you're seeing is probably not what I'm seeing. I haven't described their faces, or just how small the room is, or even which way the bed is pointing. Or which way they are on the bed, come to think of it. Even if they're naked (but let's say they are). My description of sex is probably different from how you're seeing it.
But I hope you enjoy doing what I did - a cue from the colour of the sky outside, a couple of noises and a wandering mind, leading to a description of sex that may, for all we know, be happening right now, somewhere in the world, just as you have visualised it.