I see a picture on the wall with a small heart and "live laugh love" written over there, interesting... by the look of it all, I would rule out that it's a single man's room, but it could be a matrimonial bedroom, in which case it's most likely Lena's parents. Doesn't seem unlikely, I also see a nightstand on both sides... the one on my left would be mum's (since there's a mirror on it, and also a stool) and the one on the other side would be dad's. This seems the easiest deduction to me. Clearly, I could be wrong... but if so, then I have no clue.
Not sure about that armchair facing the bed... it kinda looks like a hotel room that I saw in an old teenage love manga that I read many years ago. There was a chapter in which the boy and the girl go sleep in a hotel, and in the room there was an armchair facing the double bed (not exactly with that angle though, and also it looked farther than this from the bed).
EDIT: as much as Eva is European, from both GGGB and ORS I got the feeling that part of her inspiration is hentai and Japanese comics in general.