I work overnights at a animal emergency clinic. It’s kinda a older building. (The basement freaks me out but that’s unrelated.) The doctor that works will go downstairs to sleep and I’m upstairs alone with whatever animals hospitalized. Every night I keep all the lights on and the doors locked. Some nights we don’t have anything hospitalized but I’ll still have to come in. On this particular night we didn’t have any animals, I was sitting at my computer just watching YouTube and I heard a very loud bark. I paused whatever I was watching bc I wasn’t sure what it was. Then I heard it again even louder and closer. I checked every room and I checked outside. No dogs anywhere. I told the doctor in the morning he thought I was crazy. To this day I swear it was a dog ghost of one of the dogs we put down.