I only browse this site on my personal laptop in my room, and they the only person who is likely to burst in unannounced is my SO, who introduced me to the site in the first place. Bit different when I'm staying with my parents during the holiday's or when I come down on some weekends because people are more likely to knock and then just enter, such as my parents or friends that have just turned up. I always make sure the laptop is facing away from the door that way I can just close the webpage easily