7-11 ghost

Went across the street to 7-11 tonight to greab something. As i walked into the store i saw someone in a red 7-11 smock walk from behind the counter into the bacoroom where the bottles and supplies are (to the right) i went and grabbed my stuff and went to the counter. waited like 15 seconds. no one showed up. so i went to the door to the backroom (which was open) and knocked on it. waited about 10 seconds. no one came out. So i turned around to go to the front door and open ait to make the "dig" sound so they knew someone was in the store and as i turned there was the clerk. Short stocky he/she. "can i help you" they said/ I told them i thought they were in the backroom and that's why i was there and they said they were in the cooler and alone. freaked me out. paid for my stuff and left... half shaking as i walked back home.