Similar scenario with a guy on my course at uni. His parents, who lived in Dubai, bought a flat and covered the mortgage and his pal (they were stuck at the hip, never see one without the other etc) moved into the 2nd bedroom paying rent.
But they then turfed him out in the middle of a semester when the mum decided she wanted to come and live in Edinburgh for a few months
The two of them never spoke to each other again after that