Well, though not quite the same as yours, my brother lives in two houses. He has his own flat with his girlfriend, but he keeps his clothes here, in MY computer room. He sleeps there, then every morning comes into our house to shower and get dressed for work, waking me up.
He says it's cuz there's no room for his clothes at his flat, but I just think he likes having his meals cooked by his girlfriend, and his clothes ironed by his mum...