You and bae have been on the couch watching The Crown for what feels like days, when Netflix finally shakes you from your stupor to ask if you're "still watching." Maybe it's all the subtle sex on that particular show, or the fact that you've been cuddling for hours, but getting hygge on the couch can make you kind of aroused.
Sure, you could get up and walk to your bedroom to have sex. But you can pull off some pretty exciting positions right on your couch, so why bother? The couch is comfortable, has varying levels, and is sturdy enough to grab hold of when you need to. And, if you live with other people, there could be something thrilling about doing it on the couch where you might get caught.