Shortly after my 21st birthday, I was in my bedroom, simply lying on my bed watching TV and relaxing after a long day when I heard my dad's dog (a Teacup Chihuahua) barking. Being used to this, I ignored her for several minutes, though I eventually became annoyed with how loud she was and walked down the stairs, finding her bouncing near our front door. I looked through one of our dining room windows, finding a man (roughly six feet tall, which would tower over my 5'2") standing on my porch, just staring at the door.
After reaching out and locking the door, I yelled "Hello?" Letting him know I'd seen him, assuming he was trying break in, while trying to work up the courage to get to a phone. He knocked, then asking if he could use our phone. I said no before running down to my parents' room (a floor below the living room/dining room area) and told my dad what had happened. He said not to open the door.
When I got back up the stairs, he was gone so my brother (who had been in the basement) and I opened the door to see which way he'd went. What we didn't expect, however, was to find footprints only walking from the middle of our front yard, up to our porch, then disappearing. I still don't exactly understand what had happened, or why whoever he was never appeared again.
I know I saw him, and there were obviously footprints leading up to the porch, but there is absolutely no way possible for a living person to leave no footprints leading away from the porch. So what was he? And why did he show up at our house?