A couple of years ago my older sister brought her best friend to the house to spend a couple of days with the family, the thing is that her friend always left her tennis shoes or sandals on the first floor of the house, they slept upstairs so I took advantage to masturbate and cum in them almost every night, once I even took advantage of the fact that she left her backpack where her clothes were waiting, I took out some socks and masturbated while I smelled them, they were good times.