Hello Monika, I must say that concrete wall is fantastic! I see a large planter with a large leaved plant there.. I like Jonathan's idea, off white or shades of cream for the remaining walls and ceiling or even a subtle stone colour.. Then we need to talk textures! I think the sofa could work if you move it out a bit from the wall and layer it up with throws and add a couple of lovely cushions.. Warm woods would be nice too to balance the room.. Have you considered adding concrete to other areas of the home? There are some fantastic concrete chairs available both as a chair and bar stool.. Could be fabulous to compliment this room.. Cox and Cox did some pendant lights that were concrete with a warm edge detail.. You could create your own arrangement with a 5 wire ceiling rose and hooks.. A glass topped coffee table could be nice too.. Have a look at eBay or vintage shops.. Oh and one more thing... You can if you like the concrete wall find wallpaper for another room say that resembles what you have in the living room or even marble! It's fabulous and a feature you want to make the most out of! :))

It seems to be a simple wooden cushion sofa, I hope there is a plug point in the corner space, it can be used for charging mobiles, it would be idle if you make wooden side Table with brown tinted glass on the top a small paper / magazine holder, slim flower vase will be ok.

Any decorative ideas?

may be we can try using some marble's which give a luxury look when you have good finishing . Just an advise Best Wade robe Ideas for small space.