Haha. Ridiculous. After some complaints from my side concerning their dusty appartment, I got this feedback.
The person living there, Fatim's sister, was actually nice and we coordinated everything quite well, I thought- until now. Quite surprised and shocked by that feedback as the "real" host never complained about anything during the stay.
I cleaned what we talked about before arrival and all points mentioned above are not true (i have email evidence). I opended the windows all the time due to the nasty smell of the sisal carpet, I washed dishes, cleaned the bathroom before and after usage etc. Moreover it is untrue that surprise guests stayed- in contrary: the host's father surprisingly stayed for 2 weeks, stressful in that small kind of appartment but ok- and that I used the living room too often (this was only true during my first week when the host was not even there yet). The host had people invited, so I did not have influence on that.